Facebook ends with 500 million per month sole visitors’ mark. According to comScore’s most recent guess, in March, 484 million unique visitors were seen by the social network worldwide 2010. A year back, that number is up to 64 percent and up to 22 million from just February, 2010.

In other words, it increased by about the size of Twitter.com’s whole U.S. viewers in a single month. (ComScore puts Twitter’s worldwide audience at 79 million people).

These approximations are diverse than the Facebook’s official number of listed users, which it last simplified in February when it strikes 400 million. At its F8 conference today it might update that number to 450 million or more. The comScore numbers are inclined to be bigger than Facebook’s official numbers, which tell since not every visitor to Facebook’s site is essentially a listed user.

Some other Facebook stats from comScore:

• Worldwide page views are more than 150 percent (Yahoo) and 220 billion (Microsoft) a month.
• On standard, all visitors, people log in 11 times a month, up from 8.5 times a month a year before.
• Total time used on the site is 134 billion minutes per month, or about 7.5% of all time used up on the Internet.

[Via Techcrunch]