This image depicts the most commonly-found colors on the web's top sites—Paul Hebert did an amazing amount of analysis and this is just one of the intriguing visualizations he came up with.
Most of these are obvious staples, especially the clusters around HTML red and blue. The odd thing is the popularity of #d2b48c (triggered by the "Tan" HTML color name), which appears to be the single most popular nonblack color after #0000FF (HTML Blue) and #FF0000 (HTML Red). Google uses it somewhere (though I don't see it) Is everyone just following the leader?