My brother is having issues, too. In multiplayer, after finding players, it quites to the dashboard and says that his disc is unreadable. He was able to play 3 games yesterday afternoon but then nothing else so far. The disc looks fine. I used DVD Dr. to clean it as well but that didn't fix the issue.
The disc does have a weird "watermark" on it though. Just like StormRider99 describes.
"On the game disc. its not completely smooth looking. It has that kind of water mark window tint bubbling up look in a pretty large area of the disc not sure if that is the culprit if so."
However, I played multiplayer just fine last night in a dozen or so games with the same disc. We haven't tried Campaign yet because I'm waiting for my copy (c'mon USPS, don't fail me! :D)
He has a first launch xbox that was repaired twice - one via the RRoD and the second via a video display issue. I have a model that came out a few months later. Not sure which one.
Hope we get some more official information soon.
[Edited on 09.15.2010 10:08 AM PDT]