Here we go again... but I'll bite because I've got new input.
I have an aging Dell Inspiron 6000 (1.6GHz Celeron, 1GB RAM, 40 GB disk) that's a good test. Since my employer (D*ll) uses Linux as the environment we develop embedded code to target, I have been using Fedora 6 and 8 on my home L/T for over a year now. It worked superbly except that
Recently I managed to screw it up -- being greedy and seeing if opening up the development tree would help the aforementioned problems -- so I decided to try Ubuntu. Hated it. They've managed to completely screw up the administrative privilege system of *NIX. Can't log in as root, can't su -, same p/w for admin as for normal user, doesn't always work right. Wiped it two days after installing.
Since I have a lot of history with FreeBSD (back to 2.1.5), I decided I'd try DesktopBSD. It is purported to have the same ease of use as recent Linux distros. It does have that, indeed, including a nice GUI package/ports installer that's better than Fedora/Gnome's. It also has a well-tailored KDE install that I find to be much more stable and configurable than Gnome. However, when I tried to optimize the functionality of the OS underneath the desktop, I ran into problems getting the kernel to recompile. Do not know if that was my pilot error or inherent in the distro, but I looked and the DesktopBSD mailing lists are sparse. Wiped it and downloaded latest FreeBSD-6.3.
Okay, so I'm back to where I started. Latest FreeBSD systems preinstall more things than they used to, but you still need to allow for a good two weeks to get your system completely set up the way you want it. The FreeBSD philosophy is also NOT to do things like automounting USB keys and wireless connectivity. It's easy enough to set up these things, because the FreeBSD documentation is very good. I just wrote some one-liner shell scripts and attached them to KDE panel buttons. KDE is very easy to understand and configure, much more so than Gnome.
From an expert's perspective, the underlying mechanisms of FreeBSD are so much more efficient and tunable than (any) Linux that it's worth the effort. My clunky old Celeron blows more modern dual-core l/t's out of the water regularly. That said, it's a lot of work. There are also some packages that are painful to get working (Inkscape comes to mind), but when you do succeed, the speed of operation is awesome. My graphics subsystem is a low-end R300, but DRI and OpenGL work fine under latest ported Xorg 7.3.
So, I'm back to loving my FreeBSD and will almost certainly not switch back. However, for 90% of the rest of you, I'd have to say that Fedora 8 is a much better deal. I'd set it up to launch KDE rather than Gnome, but overall the Fedora experience I had was quite good. Ubuntu was slightly prettier, but they definitely need to take a step back and reconsider the way they've "helped" users handle root. =8^O
"There's more than one level to any answer."