comScore logoA comScore report is out which ranks the top 50 US website properties for May 2011. Yahoo! and Yahoo! Properties sits at number one with 216 million visitors, some distance from Google and Microsoft who are neck and neck for second and third spots at 179 million each, and then with quite a jump down Facebook is coming in at number four with 157 million visitors.

Although in fourth spot, Facebook is the only one that is a single site, not an amalgamation of a number of properties grouped under the same parent brand, so the rankings of the sites are slightly skewed.

The biggest jump is NBC Universal that climbed 9 positions to to spot No.33 with 31 million visitors, which can possibly be explained by the increase in popularity of some of its properties such as MSNBC.com and Hulu.com.

comscore top 50 us web properties in may 2011