The face of social networks has changed drastically in the past year. Last May, MySpace was the clear winner, in terms of US unique visitors, averaging double the visits of Facebook. We anticipated things would change at some point, but the growth is astounding. In the past year, Facebook has seen a 97% increase in monthly visitors, while MySpace suffered a 5% decrease. Even though the two giants saw a similar number of visitors this May, it seems natural for the trend to continue, leaving Facebook in the lead.

There’s a clear break in visitors between the top two social networking sites and Twitter, which is ranked third, after experiencing huge growth during the past year. Since May of 2008, Twitter’s number of monthly visitors has increased by 2,681%! Much of this can be contributed to the micro-blogging site being adopted by so many celebrities, high profile bloggers and media outlets. However, Twitter’s approx. 17.5 million unique visitors pale in comparison to the 70 million visits Facebook and MySpace received.

For more info and a list of the top twenty social networks, check out this eMarketer article.