, the Internet joint venture between News Corp and General Electric's NBC Universal, will make its catalog of TV shows and video clips available for free to anyone on the Web.

The streaming-video site, which has been in test mode since October, displays free, ad-supported shows and feature films from NBC, Fox and more than 50 media companies, including Sony Pictures, Time Warner Inc's Warner Bros Television Group, Lionsgate and Metro-Goldwyn-Mayer. Other media giants including Viacom and CBS Corp are currently in licensing deal talks with Hulu.

We won't stop until we have everything in terms of premium content. That is our mission, said Jason Kilar, Hulu's chief executive.

I just think back to the fact that 24 months ago, there wasn't anything online legally in terms of full TV episodes or films. In just 17 weeks, we have gone from nothing to over 200 premium titles.

The site launches with more than 250 television series, including current shows such as The Office and The Simpsons and classics such as Arrested Development and Buffy the Vampire Slayer. It also will offer 100 movies including The Big Lebowski and Me, Myself & Irene. Sports content from the National Basketball Association and the National Hockey League will also be available.

After launching last year, the then-unnamed company was at first viewed skeptically by industry bloggers and press, calling it a desperate attempt to compete with Google's YouTube, the dominant player in online video.

They said big media was too stupid to do anything appropriate on the web, and that NBC and Fox were incapable of partnering. Both charges have been wrong from day one, said Peter Chernin, president of News Corp, which owns Fox.

Analysts say a key challenge lies ahead for Hulu. To protect DVD and Web download sales, media companies often make TV shows and films available free on the Web for limited periods of time and then remove them. This makes Hulu's library content very unstable.

If those episodes keep disappearing, they are going to have trouble getting people to go back and recommend TV shows on Hulu to their friends, said Bobby Tulsiani, an analyst at JupiterResearch.

Big media companies predict consumers are as eager to spend long periods of time watching TV shows and movies in front of their computers as they are in front of their TV sets.

The videos can be watched on as well as on online hangouts where people already congregate and watch video, including Yahoo, America Online, Comcast's, Microsoft's MSN and MySpace.