This increase was achieved by the ability to cram 17Gb worth of data to each layer, which is more than they had anticipated when they announced back in May of 2005 that they were in development of a 45Gb solution. Industry leaders state that the previous 30Gb capacity was more than enough to fit full 1080p movies plus loads of extras on one disk. From what can be seen, it appears that Toshiba has intiated a "mine's bigger than yours" contest.
The only catch in all this is current generation HD-DVD players will not be able to read data from these new larger capacity disks, so early adopters may be in for a shock when they find out they're stuck with "only" 30Gb capacities.
Source:
Register
Written by: Dave Horvath @ 15 Jan 2007 6:18