Hitwise reports that YouTube has 50% more traffic than the rest of the video sites combined: YouTube has around 60% market share and is followed by MySpace TV (16.08%) and Google Video (7.81%). This data is restricted to the US and doesn't include the traffic generated by the embedded players.
YouTube continues to grow and Google contributed to this growth by including the site in Google Video search and by adding inline previews and thumbnails to the main search results. "Search engines are responsible for about 20% of traffic to video sites, including YouTube. Users are increasingly finding links to video pages in search engine results - and going to them," says LeeAnn Prescott from Hitwise.
It will be interesting to see if YouTube maintains this impressive growth after Google starts to include video ads and if Google uses the data obtained from its video sites to develop a better video search engine.