Sony sent out a press release this morning, announcing that they've started shipping 50GB dual layer Blu-ray Disc media in the U.S.

Sony Electronics has begun U.S. shipments of 50GB dual layer Blu-ray Disc recordable (write-once) media with AccuCORE technology.

The company also confirmed that it plans to start shipping 50GB dual layer rewritable BD media later this year.

"The arrival of 50GB Blu-ray Disc media is an important milestone in the evolution of this new format," said Mike Lucas, director of marketing for Sony Electronics' Media and Application Solutions Division. "The capacity represents more than four hours of HD quality video, at a 24 Mbps transfer rate, allowing users to take full advantage of Sony's Blu-ray Disc burners and VAIO desktop and notebook computers."
Expect to pay a premium for Sony's dual layer BD-R media. With a suggested retail price of $48, they're more twice the price of single layer BD-R discs ($20). If you'd like to read more, Sony's entire press release can be found here.