Screen Digest has reported that the DVD Forum approved TL51 HD DVD on August 31.

TL51 increases the capacity of HD DVD from 30 gigabytes on current dual layer discs to 51 gigabytes on the newly approved triple layer discs. No announcement has yet been made, but the word is that second and third generation Toshiba HD DVD players will be able to play the new triple layer discs with a firmware upgrade. Sony has used the disc capacity of Blu Ray as one of the rallying points in their marketing of the Blu Ray format, and now Toshiba can do the same as the new HD DVD discs top Blu Ray's maximum disc capacity by one gigabyte.

The new triple layer discs will also be used in hybrid discs, which allow for standard dvd and HD DVD on the same side of the disc. The hybrid disc will use one layer at 5 gigabytes for the standard DVD content, and two layers at 34 gigabytes for the HD DVD content.