Fox has joined the Blu-ray Disc Founders, who are working to establish Blu-ray as the follow on to DVD.

[...]

Sony is also part of the group, and it has entertainment and electronics arms that would both stand to gain if the technology they support were to gain mass acceptance. Sony recently purchased MGM, and movies and shows from that studio will play a key role in the development of Blu-ray, according to Sony.

Support and input from a studio is viewed as significant for the formats, since content is key for the acceptance of any form of media.
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