"There seems to be no end in sight when it comes to the popularity of social networking sites. Myspace.com surpassed the 50 million unique visitor-mark in May, an increase of seven percent since April. In addition, Youtube nearly doubled its traffic in May, reaching 12.6 million visitors, while Classmates.com reached 14.7 million visitors, and Facebook.com captured just over 14 million visitors."
According to comScore YouTube had 12.6 million unique visitors in May (up from 6.6M and so putting it just outside the top 50 properties on the Web), Google Video 7M, and Yahoo! Video 4.2M. YouTube was in fact the fifth most "Gaining Property" across all the sites comScore tracks, by percentage change in unique visitors, from April to May! Here's the trend chart, comparing YouTube's success with the far more static growth of Yahoo Videos and Google Videos:
Alexa.com shows a similar trend, but suspiciously their stats have YouTube with the same reach as MySpace (which obviously isn't right):
I'd be interested to see Hitwise's chart for May 06, because last time they did one (in December 05) they had Yahoo way out in front - but at that time YouTube was just starting it's big push:
So in the space of just 6 months YouTube has not only overtaken Yahoo Video as the most popular Web video-sharing service on the planet, but it's now approx 3 times as big as Yahoo's product! That just shows (once again) how quickly the status quo can change on the Web.