Now playing on Facebook: “The Dark Knight”

One of the biggest online video sites in the world (not to mention a fairly big deal in the social-networking arena) is finally renting movies. First up: "The Dark Knight," Christopher Nolan's summer 2008 blockbuster.

You can go ahead and rent "The Dark Knight" right now on the official "Batman: The Dark Knight" Facebook page.

A 48-hour rental period (twice as long as the usual 24-hour window offered by the likes of iTunes, Amazon, and Vudu) costs 30 Facebook credits, or $3 here in the U.S. You'll have to install the "Dark Knight" viewer application (which requests access to your publicly shared Facebook information) before the feature begins.

Once you pony up the cash, just hit the "play" button to begin the show, which starts streaming directly in the browser. There's a full-screen option and a slider for jumping forward or back during playback, along with a volume control—otherwise, that's it.

This marks the first time that a Hollywood studio has rented a movie directly through Facebook, with Warner Brothers telling The Hollywood Reporter that this initial "Dark Knight" rental is just a test.

That much is obvious, given the blocky, jerky video quality on my Facebook page (and over a pretty fast broadband connection, by the way)—and no, three's no HD option, nor any way to stream the movie to an HDTV (short of hooking up your PC or laptop directly to the screen). Warner Brothers will have to do better than this if it expects to actually make hay with video rentals through Facebook.

Still, the partnership makes sense, with All Things Digital's Peter Kafka pointing out that with its 600 million members and unmatched arsenal of social networking tools (indeed, Facebook "is *the* social hook," Kafka writes), Facebook seems like an attractive platform the big movie studios. "The only thing odd about this combination is that it's taken this long to come about," adds Kafka—very true.

Warner Brothers has been busy testing the digital distribution waters in the past several weeks. Just last month, it make headlines by releasing iOS apps that included complete downloads for both "The Dark Knight" and "Inception," allowing the studio to sell digital versions of the movies in countries where the iTunes video store isn't available.

So, assuming the big Hollywood studios manage to (substantially) boost the quality of their video streams through Facebook … could you see yourself turning to the world's largest social network for Net-based movie rentals? Or would you rather stick to existing online video stores like iTunes and Amazon?

Related:
Warner Bros. to Rent Movies Digitally on Facebook, Starting With 'Dark Knight' [The Hollywood Reporter]
YouTube, Netflix, Hulu: Meet Facebook [All Things Digital]

— Ben Patterson is a technology blogger for Yahoo! News.

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