Joost has launched a web-based video service that uses Flash.

Until now, Joost, which works on Mac OS X and Windows, has used a video playback mechanism based around H.264, also used by YouTube and Apple's iTunes Store.

Joost combines tens of thousands of videos, including many popular TV shows and music videos, with social networking capabilities. Users can become each other's friends, make recommendations through email and through groups that share similar interests; they can also make comments on videos, 'shouts' and tags. Those features and functionalities have been exposed through the Flash-based interface.

JoostFeed is a feed service that aggregates all of the activities happening on Joost; it's viewable on Joost and can be exported to any social tool or website. Joost has also partnered with third-party platforms including Delicious, Digg, Meebo and others. Joost will also soon implement Facebook Connect.