Well I just tested out OpenSUSE 10.2, and I gotta say I loved it. It's not quite as glamorous as the Novell's SUSE Linux Enterprise Desktop 10 (which only costs 47 Euros, approx. $60 USD), but it's pretty amazing.
I had a bit of trouble when I uninstalled it, but I sorted that problem out. Basically Linux sets up GRUB (a boot interface) on the MBR of the primary drive, but it doesn't back up the original MBR. I just had to reset it with FDISK.
Anyway, the OS is great on all fronts, but it takes a bit of getting used to. The only real problem is the lack of software and games.. Every thing's made for Windows.
I'm seriously considering a dual-boot (OpenSUSE makes that easy too).
Man, screw Vista! I ain't gonna switch unless I have to in 2-3 years!
Anyone else familiar with Linux desktops?