Here is the list of Ad Planner Top 1000, the list of the largest 1000 sites worldwide, based on Unique Visitors (users), as measured by Ad Planner.
note: this list excludes adult sites, certain Google sites, ad networks, domains that don’t have publicly visible content.
Rank Site – Page Views
1 facebook.com- 570,000,000,000
2 yahoo.com – 70,000,000,000
3 live.com – 39,000,000,000
4 wikipedia.org – 7,900,000,000
5 msn.com – 11,000,000,000
6 microsoft.com- 3,300,000,000
7 blogspot.com – 4,400,000,000
8 baidu.com 27,000,000,000
9 qq.com – 25,000,000,000
10 mozilla.com- 140,000,000
Check full list of The 1000 most-visited sites on the web http://www.google.com/adplanner/static/top1000/