The latest Dashboard preview program has begun to roll out to those accepted in the opt-in program, but apparently not much is different according to reports.
The only immediate change is the addition of an ‘Xbox beta’ channel with three items. There are two groups among testers divided by the update method used.
The new ‘Xbox Beta’ channel has ‘Xbox Beta Program - Preview LIVE Update’, ‘New Features’ and ‘Help and Tips’ within it. The two groups are decided by the update method which is either online (and eligible for a free Halo: Reach copy) or via a disc.
Microsoft are ”finalizing the logistics to distribute the discs now.”