Fedora Core 1 was tolerable. When they released Fedora Core 2 with SELinux
turned on by default was when it was a nightmare. I've got a Fedora 10 box
beside me and it is actually quite nice. Most of my workstations are Ubuntu
thought because it "just works TM".
Ubuntu doesn't belong on a server, RHEL or CentOS does. Just my 2 cents.