As you know.
Worst disks? Maxtor. No question. I RMA more of these than any other.
Next up, IBM DeskStar drives, and Fujitsu. I don't care how good Fujitsu drives are - their stupid warranty arrangement (which makes it extremely difficult to RMA a drive) means that I hate them.
Seagate and WD are on a par for reliability, and also oddly enough for having the most straightforward RMA procedure.
For SCSI disks, I'm currently seeing low failure rates on Quantum Atlas and Seagate Cheetah disks. The IBM SCSI disks are just as crap as their IDE ones.
Interestingly enough, a lot of the big disk manufacturers are, at least for IDE drives, dropping their warranty periods to 1 year. WD aren't doing this. I guess I'm buying WD at home next time.