After spending way too much time trying to track down various Ubuntu 9.10 problems I've finally punted and switched to Fedore Core 12.
I was initially reluctant to do this because I had such bad experiences with previous versions. The problem is that I didn't want to run CentOS 5.4 as a desktop operating system because of the endless versioning problems I would run into.
So I installed Fedore Core 12 on the second drive and am happy to report it's a MUCH more stable distribution than Ubuntu. Strangely, it also seems to be significantly faster. I'm not sure why.
However, I did run into an issue when trying to get my nVidia card to work. After going through the steps of installing the proprietary driver VMware would no longer install. I wrote up a little article on the subject here:
http://yml.com/fv-b-1-546/Fedora-Core-12-vmware-worksta...

OK, based on your experience, I may have to look at Fedora again...

I can give you an overview of what I've found the next time you come over. It's set up much the way CentOS is and this time seems to run really well. It's snappy and the GUI is nicely put together. I'm actually running Gnome and it's not too bad now.

What do you mean by "versioning problems"?

Most, if not all, desktop software now relies on updated libraries. Gnome, gtk+, glib, kde, etc. etc.

Redhat does not produce updated quality controlled libraries for RHEL (which CentOS is based on). So you end up having to install bunches of libraries configured and compiled by third parties.

Then it can happen that they don't build the RPM's right. So maybe 1 program requires version 1.2.3 of a particular library but another program clobbers that libraries and installs a completely different version, etc. Dependencies break and you end up having a mess.