Since the leading search engine Google's own social networking site Google+ was launched in June, it has grown a lot and, according to some reports, it will surpass Twitter and LinkedIn as the No. 2 social media network within one year.

About 13 percent of U.S. adults has signed up Google+ and it may reach 22 percent within one year, according to a poll of over a thousand U.S. adults by Bloomberg and YouGov. Twitter's users will rise 3 percent of the U.S. population to 20 percent, LinkedIn's users will increase 2 percent to 20 percent of the U.S. population. However, Facebook may decrease 2 percent to 69 percent.

According to Facebook's latest release, as of July 2011, the social media giant has about 750 million active users. But the monthly growth of Facebook users has declined from 13.33 percent (April 2009) to 2.54 percent (July 2011). On Facebook, any public content is searchable. The feature of organizing events is widely used on Facebook, which the Google+ does not have.

Twitter, launched in July, 2006, rapidly gained worldwide popularity with 200 million users as of 2011. Twitter enables users to subscribe to other users' tweets and allows celebrities to get their accounts verified.

LinkedIn, launched in May 2003, reportedly had more than 100 million registered users as of March 2011. LinkedIn allows registered users to maintain a list of contact details of people with whom they have some level of relationship, and also allows users to research companies with which they may be interested in working.

Who will have more users after one year: Google+, Facebook, Twitter or Linkedln? Leave your comments below.

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