More evidence that the major video-aggregation sites are morphing into hubs and distributors of content rather than pure destination sites: Joost today announced an agreement to make its library of over 50,000 videos available to users of the homepage of Belgian social-networking site Netlog. According to Quantcast, Netlog reaches about 25 million unique visitors a month, so Joost gains immediate access to a sizable new audience. Joost’s move follows a similar one by Hulu ,which said it will start playing its videos on the social-networking site dailymotion.com.

Both Hulu and Joost have embed features that let users play videos on their own websites through each site’s player, but wholesale content distribution deals with outside sites haven’t been common. Typically in these kinds of distribution deals, both parties likely have the ability to sell advertising on the content.

Joost has had some some false starts with its service: The company switched to streaming online only in late 2008, after users complained about its P2P streaming. 

• Joost Drops Video App, P2P Features; Website Viewing Is The Main Concentration