Hardware.Info has done an investigation into reports of circular scratches on discs caused by the Xbox 360 itself. This report struck close to home for me as I have been a victim of this (and luckily spent 2 dollars on my EB guarentee!).
The report is very interesting and a good read for Xbox 360 owners, but I wanted to add my own experience and what I believe is a solution if you have this problem.
The problems seem to stem from the console being nudged at all during use. If it is, you can keep playing and never notice anything, but sometimes when you eject the disk you find a circular gouge into it.
For me, this problem is avoidable in one simple way: lay the console down when you use it. I found this happened standing up. The thing is less sturdy and more prone to disaster. No amount of nudging when on its side has replicated this problem locally.
Check out the article here.
