Xbox 360 preview program it's time to start camping out by your mailbox and pestering your delivery person -- the update discs are shipping. A few lucky gamers now have their sneak peak at the next Xbox Live update and free copy of Halo: Reach in hand, and one was kind enough to send us the shot above to prove it. The disc bears a serious warning though: do not try and install it on a non-preview approved system. Doing so will completely disable Xbox Live until the update is officially released, which may be months away. So, if your friend got a disc don't even think about trying to mooch your way into the beta program. After all, what fun is playing Halo if you're stuck trying to save Reach by yourself?