Upgrade Experience not Stellar...
but it wasn't fraught with failure as this article might suggest. My graphics worked just fine, my hard drives worked just fine, and the installed kernel is one of the newer ones, at 2.6.31-14. I suppose it goes without saying that I did a clean install.
This is not to say that I didn't have problems. Pulseaudio is a mess and Network-Manager, which worked flawlessly (for the very first time) in Jaunty, is again broken in Karmic. Oh, and installing the proprietary driver for my soft-modem made my sound card "magically" disappear. But none of my issues have been severe enough to make me consider rolling back, though that is always an option I have.
For those of you complaining about having to go through this sort of pain every six months, I have but one question for you: Why? Why put yourself through all of that every six months? Ubuntu has a LTS system for a reason. The non-LTS releases should be viewed as the bleeding-edge, unstable, "early-adopter" versions, while the LTS releases are made specifically for those of you who "just need a computer to work" without all the futzing around. If you don't want to get your hands dirty over a weekend every six months, then don't. But if you DO choose to upgrade every six months rather than every two years, then be prepared to make Launchpad your best friend.