During CES 2007, we reported that Toshiba had created a 51GB HD DVD (I said 50 gig at the time, I was wrong), though they were unsure if their disc would work in current HD DVD players.
They're obviously keen to pursue this triple-layer one-upmanship (over Blu-ray), as they've announced that they will be submitting specifications for the disc to the standard's overseer.
Despite a press release from the company claiming that "Toshiba has confirmed the disc structure and its successful operation", the technical feasibility for real-world (consumer) use has not yet been proven. Despite this, they hope to be launch the format by the end of 2007.
Getting these triple layer discs to play in existing HD DVD players will surely be critical to their success. Who wants yet another potential for obsolescence? Given that the triple layer disc claims to provide 51GB of storage, and not 45GB (which might be logical given that single layer HD DVDs are 15GB and dual layer are 30GB), there must already be some incompatibility between the formats.
We'll find out more as the specification is revealed later in the year.

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