RANT and/or Public Service Announcement. So I installed OS X recently; which I happen to like a lot -- somewhat suprisingly! Being an old mac hand, I was prepared to grumble a lot. Not that there isn't anything to grumble about, but overall, I'm impressed.
BUT! The damn thing had a major meltdown last friday night. Kernel Panics galore! Did not make me very happy, and there seemed to be very little good advice available. MacAdam, a local SF mac store, told me to reformat my drive and reinstall, Apple gave them no better information! But then the guy said, "The panics still might happen," which tipped me off to keep looking for answers.
And lo! Buried in discussion boards on Apple, I found my answer. My mouse had died! OS X is a nice stable operating system for the most part, but it can't handle the damn mouse failing. Geeze! A new mouse, and all those Kernel Panics went away.
So if you have one and see com.apple.driver.AppleUSBMouse, try changing your mouse!