So far, 13% of US adults are signed up for Google Plus, and it’s speculated that the social network could hit 22% in a year, which would pass LinkedIn and Twitter as the number two social networks. This information is according to a new study.

The study is based on a YouGov and Bloomberg poll of 1,003 USadults from July 29^th to August 2^nd. It revealed that 71% of US adults are Facebook users, but that number will drop to 69% within the next year. 31% of Google Plus users say that they’ve abandoned their Google Plus accounts or never posted anything on them. However, among the people who used both services, 30% say that they plan to cut down the time they spend on Facebook.

LinkedIn and Twitter are expected to continue to grow. LinkedIn is supposed to add 2% of theUSpopulation over the next year, and Twitter is expected to add 3%. That would bring LinkedIn users up to 20% of theUSpopulation and Twitter up to 20% as well. It will be interesting to see if these results prove to be true.

Google Plus is continuing to set records as the fastest-growing social network in history, but Google’s social force is starting to show signs of losing steam.

On Tuesday, Paul Allen, co-founder of Ancestry.com, posted his most recent analysis of Google Plus’s growth on his Google Plus account. According to his analysis, Google Plus, which is a Facebook competitor from the search engine giant, will likely reach 18 million users by the end of Tuesday. However, the growth rate has dropped from its peak by 50%.

Allen said in his post on Google Plus, “last week we saw two days where more than 2 million signed up in a single day. If that rate had continued, Google Plus would have reached 20 million users by last Sunday night. But the last four days have averaged only 948,000 new users, and yesterday the site added only 763,000. Yesterday’s growth of 4.47% was the slowest viral growth since Google opened up invites back on July 6.”

Many users are now wondering why Google Plus’s growth is slowing down. Google Trends indicates that the buzz around Google Plus has died down some, which is only natural for a major news item. Allen does point out that Google Plus is still invite-only, and it has not been promoted by any of its other properties. It’s very possible that the growth of Google Plus will skyrocket once it is promoted on Google.com or YouTube.

It’s estimated by Allen that Google Plus hit the 10 million user mark sometime on July 12^th or 13^th. Larry Page, Google CEO, confirmed that Google Plus had more than 10 million users during an investor earnings call on July 14^th. Mark Zuckerberg, Facebook creator, now has more than 250,000 followers making him the most followed user on Google Plus.

The buzz around Google Plus is clearly a lot bigger than the buzz was for Google Buzz, one of Google’s failed attempts at social networking. However, Google Plus is not monopolizing social media conversations on the net.

That is the message behind the new research from Sysomos, a social media analytics firm. At Mashable’s request, Sysomos compared the social media chatter for Google Buzz when it was launched back in February 2010 to Google Plus’s introduction earlier this summer. There is little comparison between these two launches. According to Sysomos, the mentions of Google Buzz peaked at 150,000 while Google Plus social media mentions have surpassed 250,000.

Since its launch a few weeks ago, Google Plus has been mentioned in 106,000 blogs, 30,000 news stories, and 1.9 million tweets. 85% of these mentions were positive, according to Sysomos. However, Google Plus mentions are nowhere near the level of Facebook and Twitter mentions. Each of these social networking sites get about twice as many mentions per day than Google Plus.

While it may seem like everyone is talking about Google Plus, that could just be in certain circles. In the mainstream, it’s not quite there yet.

Apparently, according to Google Plus stat trackers, three quarters (or more) of Google Plus users are male. SocialStatistics, a third-party site that gathers data from select profiles, pegs the percentage of male users at 86.8% while FindPeopleOnPlus says men constitute 73.7% of Google Plus users.

FindPeopleOnPlus also reported that 95% of the Google Plus users who say they are “looking for love” are male. Of the users sampled, 25,000 identify themselves a single, 12,000 say they are in a relationship, 19,000 say they are married, and the vast majority don’t identify their relationship status.

60% of users identify themselves as either web developers or software engineers, which paints a stereotypical picture of Google Plus users, nerdy guys who understand technology and don’t mind killing time by setting up circles of friends.

It is true that early adopters of any new technology are typically mostly male. However, Google Plus will have to appeal to a mainstream audience if it is going to reach mass adoption anytime soon. Consider the gender breakdown for Facebook, for instance. This social network is very close to a 50-50 split between men and women. Google Plus is no longer making it necessary for users to identify their gender, though, which may make statistics less accurate in the future.

One of this blog’s reader, Laura Trejo, feels that Google plus {she used to call it google -} is a big time failure and is a mere facebook clone. Her arguments are true to some extent as one cant say that google plus is a big hit just by considering the fact that it has reached the 10 million users mark in ten days. Yes, I do agree that google plus has reached this figure far quicker than facebook or twitter but most of google plus’s users are early adopters and we must agree that google plus hasn’t been seriously tested yet.

Google Plus’s strategic and orchestrated launch has been nearly flawless, certainly more successful than Google’s previous attempts at social networking. Thanks to Google’s failure with Google Buzz, early reviews of Google Plus were positive but reserved. Like clockwork though, technology celebrities like Kevin Rose and Robert Scoble started flooding Google’s new social network and before long, they were all singing its praises.

Like Gmail, Google released Google Plus invites in small spurts at first, which made everyone want to get in with an invite. This gave Google Plus a feeling of exclusivity. This resulted in 10 million users in only two weeks with high user engagement on Google Plus with many users reported they get more responses on Google Plus than they do on Twitter or Facebook. Google Plus certainly has momentum.

The unfortunate part of this is that the momentum is blinding the press and Google Plus users to the reality that Google Plus is dominated almost entirely by early adopters who tend not to be great predictors of the success of a social network.

If you take a look at other previous social media projects that were embraced by early adopters, you can get a better idea of this concept. If you think about the technology adoption lifecycle andRogers’ bell curve, a sociological model developed in the 1950s to predict the normal distribution of technology adoption, you can better understand this. Early adopters and innovators make up the first 16% of any given population that accepts a new technology. They tend to be members of the community that aren’t afraid to try new things, more risk-oriented people. This still leaves 84% of the population to adopt new technology.

If you look at Facebook, for example, which currently has 750 million users and you take into account that Mark Zuckerberg, Facebook CEO and creator, has stated that he believes Facebook has hit critical mass, you can come up with some rough numbers to predict the future of Google Plus. Assuming 750 million users is the potential market for the adoption of a social media service, that would mean that (according to this math), the first 120 million users are considered early adopters for social networking. That is certainly a long way from Google Plus’s current 10 million users.

While Google Plus is riding a tidal wave of momentum at the moment, it’s still not as mainstream as Facebook. It’s hard to predict exactly what will happen with Google Plus and if it will sustain its growth past the early adopters.

Larry Page, Google CEO, headlined Google’s earnings call today and revealed some interesting statistics on Google’s most recent product. According to Page, the new management structure is “working together fabulously” and helping to achieve Google’s goal of making “sharing on web like sharing in real life.”

Page talks about the popularity of Google Circles and how people are particularly enjoying this future. Page also explains how Google Plus now has over 10 million users and these users share and receive 1 billion items per day.  Yesterday, twitter revealed that 350 billion items are shared in their network everyday. Google plus certainly has a lot of catching up to do.

To put this into perspective, in just two weeks, Google Plus has reached 10 million users, 1.3% of Facebook’s 750 million users. This is especially remarkable if you think about how long it has taken Facebook to grow so popular and the general flow of social networking sites becoming popular and then being taken over by something else, from Livejournal to Myspace to Facebook to Twitter and now Google Plus.

Google Plus has surely been Google’s most aggressive social networking product so far, and clearly it is already succeeding in terms of users and how engaged those users are.

It’s possible that the new Google plus is one of the fastest-growing networks ever. According to one estimate, the site has already reached 10 million users.

Ancestry.com founder Paul Allen (who should not be mistaken for Microsoft co-founder Paul Allen) has now developed an interesting methodology to calculate the number of new users on Google plus. He has sampled a number of surnames from the US Census Bureau data and compared that to surnames of Google plus users. By comparing the surname popularity in the US population with the number of users on Google plus with each surname, he can then take an estimated guess at the percentage of the US population that has signed up for Google plus. Then he circulated a ratio of US to non-US users to then estimate the number of Google plus users worldwide.

According to Allen’s estimated numbers, Google plus has 2.2 million users who have joined in the past 34 hours and a grand total of approximately 9.5 million users worldwide. This is amazing growth even for an internet giant like Google. It’s hard to think of another social network that reached so many numbers so shortly after its launch. With both Myspace and Facebook, the growth was a much slower and more gradual thing. Previous social networks became popular over a period of time. With the already hugely popular Google, though, and the buzz created around Google plus before it even launched, it’s no wonder that Google plus has become wildly popular practically overnight.

These numbers are obviously unofficial and Google has not yet commented on the number of users. While these specific numbers should be taken with a grain of salt, it’s easy to see that Google plus is quickly becoming a popular social network.