In my previous post I indicated an upgrade probelm with this process. My procedure was incorrect. I attempted to upgrade a 5.1 system with the Centos 5.2 dvd. It failed, possibly due to my selection to update the grub installation.
A simple update/upgrade using yum works fine. I have update two servers using yum update and both function perfectly. Perhaps a reason for the popularity of Centos!
I have upgraded my desktop to Centos 5.2 (64). First I tried upgrading (5.1) but grub would not install correctly. I was unable to repair grub and ended up removing the old grub from the mbr of the hd. It took a couple of fresh installs to correct the grub issue.
I notice some changes, Firefox 3, etc but mainly evolution rather than revolution (as you would expect). Kernel is still the 2.6.18 series (2.6.18-92.1.1). I do not notice anything unusual. It installs with 4mb memory without problems. No kernel tweeks are necessary (as in Ubuntu) to correct acpi or iommu problems.
I am reluctant to remotely upgrade my Centos 5.1 server, as I had problems with my initial install locally.