Google+ may not boast a user base with numbers as high as Facebook, but it had had one of its strongest months ever just recently. According to a section of media analysts, the search engine giant’s social site is well on track to scale 400 million mark in terms of total users.

Experian Hitwise just recently sent out a tweet that the fledgling social networking platform experienced quite an impressive jump in traffic volume and more than doubled the number in a matter of month. The research agency tweeted: “Google+ total US visits reach more than 49 million in Dec, biggest month to date & up 55percent”. It pointed out that total US visits for the site had grown eight out of the previous nine weeks.

Though Google+ has not reacted publicly about its rising membership numbers, analysts are drawing their own conclusions. The founder of Ancestry.com, Paul Allen, stated that the social site had already crossed the 62 million mark, almost 25 percent of the site’s total user base generated in December alone.

The growth rate is indeed praiseworthy since Facebook had not passed the 60 million members’ marl until almost four years after its launch. And at this rate, experts like Paul Allen expect Google+ to surpass 400 million users by the end of the year. For record, Facebook has over 800 million active members. The growth of Google+ can be attributed to the fact that it has become easier to access it on compatible Android devices, with millions of them being purchased each day. Google integrates its Android devices with Google+.

Incidentally, Facebook was the top-visited Website for the second year and accounted for 10.29 percent in terms of all online visits in the U.S. (from January until November 2011), according to another study done by Experian Hitwise. This marks almost a 15 percent jump from the number of visitors in 2010, the findings suggest. Google.com is ranked second on the list with 7.70 percent of total visits, which incidentally is an increase of 7 percent, followed by its video site YouTube (3.17 percent increase), Yahoo Mail (2.95 percent rise) and Yahoo! (2.47 percent increase).

The combination of all Google properties accounted for almost 12 percent of all U.S. visits on the Web – a solid 22 percent rise in 2011compared with the previous year. On the other hand, Facebook properties accounted for close to 9 percent, whereas Yahoo! properties grabbed nearly 7 percent of all U.S. visits.

According to the report, these top 10 sites (the rest of them being MSN, Myspace, Mail Live, Search Yahoo and Bing) accounted for not less than one third of all U.S. visits, registering a flattish move compared with 2010. Among the fastest-moving search terms on basis of absolute change in 2011 were hurricane Irene path, osama bin laden dead, bin laden wives, les paul, apophis asteroid, nick ashford dies, sheen dumped, and amber cole.