YouTube said that its videos account for 60% of all videos watched online in the US. It has almost 20 million visitors to the site each month, according to Nielsen/NetRatings.

Videos are downloaded free from the site and the company is still working on developing advertising and other means of generating revenue to support the business.

MySpace, the social networking site popular with teenagers, has close to a 19% share of the market, according to Hitwise.

Yahoo, Microsoft's MSN, Google and AOL each have 3 to 5% of the video search market.