The testing discs for those chosen to take part in the Xbox 360 firmware preview are starting to hit, according to multiple tipsters, giving us a bit of insight on Microsoft's testing methods. As expected, the test disc itself has Halo: Reach, making it both the testing model and reward for Microsoft's army of volunteer tinkerers. It warns not to use it on unauthorized systems, however, since that will "disable access to Xbox Live."

A sheet accompanying the disc asks preview testers to play at least one hour of the Halo: Reach preview disc, along with any other games, music CDs, and DVDs. For the purposes of testing, it specifies to play games from their respective discs, rather than from an installation on the HDD.

The company is seeking feedback on any bugs from the update itself, scratches on discs, and error codes. This all seems to lend credence to the widely-held rumor that the new disc format adds roughly one gig of hard drive space by removing some of the excess data, like anti-piracy measures, from the disc.