Microsoft's 'updated Xbox 360 disc format' to add an extra gigabyte?

As you'll recall from yesterday, there was one small detail that stood out in Microsoft's announcement of a new preview program for the Xbox 360 -- namely, word that the latest system update would bring with it an "updated Xbox 360 disc format." That naturally prompted plenty of speculation, and Eurogamer now says it has heard from a "highly placed development source" who has confirmed that the new disc format actually adds 1GB of storage space to Xbox 360 discs. As the site notes, the Xbox 360's current disc format tops out at just 6.8GB, which still leaves some room to play around with on a standard dual-layer DVD. That would also explain the free copy of Halo: Reach that Microsoft is giving out to everyone accepted into the preview program -- can't really test a new disc format without some new discs now, can you?