The saddest part of all this is that if Parallels was properly tested and all the features worked as advertised, it would be hard not to recommend it over VMWare Fusion.
On Linux it seems, the Parallels installer assistant is the problem. On Parallels, you're often dealing with mouse input and screen size issues until you get the tools installed and reboot. VMWare installs with all client OSes are smooth, even before you get the VMWare Tools installed. Both the kernel extension and VMWare Fusion 3 application are 64-bit. Even in Windows XP 32-bit, it threw up three BSODs in less than a week of using it. This is in sharp contrast to Parallels Desktop 5, which has a laundry list of big issues with everything new and old.
VMWare Fusion 3's problems are limited to its new OpenGL driver but everything else is remarkably stable and reliable. It's no stretch to say that Parallels Desktop 5 has a lot of issues.
Here is where the two big dogs of Mac virtualization shine: Parallels Advantages: So I can be confident that these failings are exclusively Parallels Desktop 5's fault. I run very well-maintained machines, and, before the review, I made sure to run permission fixes and uninstall VMWare in case that could potentially interfere. So zero for two with 10.6 Server is not what I'd call a great score. The documentation states that shared folders do not work in 64-bit 10.6 Server virtual machines but “they work fine” in 32-bit kernel mode.