Multiple Monitors
I've found that multiple monitors depends very much on what chipset I'm using. On an ATI board it was a pain in the ass, buggy as hell, kept changing my settings. Hated it. Had an nVidia board about the same power lying around. Swapped it in and it worked perfectly with multiple monitors, though each one has its own mouse cursor for some reason...
I do agree with other posters that there are some basic things that just aren't available as easy GUI-based config options, but I *do* see developments in these with every release. Sticking with monitors, compare the dialog for configuring these in Karmic with the one in Hardy.
It still pisses me off that KDE doesn't have an option to turn off tapping though. I mean, for the love of God! Surely there should be an option built for that long before the options to change colours, themes, etc.