Netflix on Monday said it has added South Park and other TV shows from Viacom's MTV Networks to the movie renter's streaming service for subscribers who want to watch online video on their PCs or digital TVs.

The latest offering boosts Netflix's library of movies and TV episodes available through the online service the company launched more than a year ago. The service is available only to subscribers of Netflix's by-mail DVD rental service, but the company has said it will eventually offer the option of online-only movie rentals.

In the MTV deal, Netflix is offering the first nine seasons of South Park, 139 episodes in all. In addition, Netflix is offering episodes from a number of hit Nickelodeon shows, including SpongeBob SquarePants, iCarly, Blues Cross, Dora the Explorer, and True Jackson, VP.

The deal marks an expansion of Netflix's partnership with MTV, which offers some of its content on DVD through Netflix.

Since launching its streaming service, Netflix has made it available on Microsoft's Xbox video game console, set-top boxes from TiVo and Roku, and devices made by LG Electronics and Samsung. Netflix offers its 10 million subscribers more than 12,000 movies and TV episodes online out of its library of 100,000 titles. Growth in its video-streaming service was a big contributor to Netflix's stronger-than-expected quarterly results, released in January. Reflecting the growing popularity is the success Netflix has had on the Xbox.

Microsoft said 1 million subscribers of the Xbox Live online service have activated the Netflix application and have watched 1.5 billion minutes of entertainment since the service was launched last November.

Netflix rivals Blockbuster and Apple iTunes also offer movies online. Like Netflix, Blockbuster has partnerships with hardware makers to offer its service on Internet-connected TVs. Apple offers a similar feature through its Apple TV set-top box.

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