If you're planning on buying it anyway, and don't plan on waiting in line at the Apple store the day it comes out, maybe you'd like to buy it at Amazon and throw us a referral? They've set up a special landing page for you to get all the details - right over here (The W at Amazon).
Keep in mind this'll only work on Intels - if you have a PowerPC, you're stuck at 10.5 (and probably need to think about upgrading some time in the next 24 months).
Both the CD-R & DVD-ROM are flaking out the same? And they worked at some point with whatever burn speed you had it set at? Did they both start flaking out at the same time (like with an OS upgrade or security update?) BTW is this a PC or a Mac?