Compete , an onlinestatistics site, notes that the line-up of most visited video sites remains more or less the same (in descending order): Google (including Youtube), Myspace, MSN Videos, Yahoo!, Aol... and then the second tier includes ManiaTV!, StupidVideos, Break, Addicting Clips (part of Atom Films) and Pure Video.
Why is this important? Aside from helping you with your afternoon video habit, this is key since if you decide to sell your video content online, and and you're paid per view (the most common option today), your profit is going to be disproportionately due to the size of the viewership. Too bad that none of the big players offer revenue sharing with content providers.