It's been some time since X made me hate computing, but it happened again today (well, yesterday into the early hours of today, actually.
I got the stupid idea to upgrade to squeeze from lenny yesterday. I was at work, but it was actually a holiday in the USA, and I figured it would be a good time to do some sysadmin work instead of my usual work.
I admittedly had some things to fix that were my fault: I had backports and other mess installed, but upon removing, the upgrade itself was more-or-less smooth. I faced only a minor problem with my MD device for /boot not starting properly, but the upgrade warned me that I needed to switch to properly using the UUIDs for my RAID arrays, and once I corrected that, all booted fine, even with GRUB2 on my old hardware.