Gary, for what it's worth, my upgraded Sawtooth doesn't show any serial number in the ASP, and I've had no issues whatsoever with 10.2.4.
If you look at the those Apple Discussions carefully, you'll see that it's actually only a couple of people with the "serial number theory"...and they've both been posting in several threads.
What the lack of serial number in the ASP indicates is beyond me - in my case, it may have something to do with the processor upgrade...and no, I'm not going to put my old processor back in just to test this theory!
However, I think it sounds like your Mac is in good hands, and your problems may well be something to do with the Superdrive.
The people (the two chief complainants anyway) at the Apple Discussions seem to have some sort of hardware issue going on, since both have tried their drives elsewhere, installed Jag and then gotten kernel panics when the drives are put back in the troublesome machines. All other removable hardware has been switched, tested, whatever. Hardware issue of some sort probably...not likely a firmware thing with so few individuals reporting the problem. No fun when your machine is out of warranty!
