After setting up Apple Boot Camp completely, I decided to give Parallels Workstation Beta a try.
I installed WindowsXP on it and almost finished setting up a fully functional environment. The first thing that strikes you is that it's amazingly fast. Apart from the occasional minor lag in screen updates, the CPU seems to run at full speed. However, when I installed TortoiseSVN, something went wrong. Windows started to spit out bad memory access errors and Explorer failed to work properly anymore. At that point I was unable to do anything with the virtual machine since I had no working shell for Windows available, I erased it.
The main reason for me to run a virtual machine is to be able to access Oracle Database 10g Release 2 under MacOSX (no, the PPC version doesn't work under Rosetta). I decided to create a virtual machine for Ubuntu Linux 5.10 next.
The Linux installation went fine and the entire Oracle database together with the creation of an initial database took only 10 minutes. That's really a proof of how fast the virtual machine is. Sadly however, for my purpose, Parallels turns out to be unusable for me. It seems that there's a bug that makes your MacOSX kernel panic when there's traffic on the bridged network interface (either from the VM or from the MacOSX primary OS). I get this crash consistently whenever I try to access the VM Oracle from MacOSX.

I'm eagerly waiting for the next beta of Parallels Workstation. I hope they'll fix the bug that crashes your entire machine soon. When that's done, I'll certainly buy a license of Parallels since the speed is simply mind blowing. Even VMware on Linux never felt this fast to me. You have a wonderful and promising product here, Parallels!