Why dont you go and take a look for yourself,if you do a google search you will find the link then all you do is take a look at the site and it will tell you,its called getting of your backside and looking rather than asking other people to do the work for you. Then you can come back and tell us all !!!
here is some top sites list google.comfacebook.com youtube.com yahoo.com wikipedia.org live.com twitter.com qq.com amazone.com
This is google.com. The post would be more important if you checked first and come up with the answer.
According to alexa.com it is as of 6/17/12 (happy fathers day) 1. Google 2. Facebook 3. Youtube 4. Yahoo