I agree with the previous two posters. Been playing UT for more than a decade now. UT3 sucks. It's pretty, but not a fun game. The linux port was confirmed early on, and there was talk of even supporting UnrealED under linux too. When release-day came, they didn't even have a linux SERVER ready, which meant that the 80% or so of the servers normally used for UT games couldn't even host the new version.
That right there was pretty much the stamp of authority that there would be no UT3 client linux port. When you don't think the most popular server architecture is worth porting UT3 to for release day, there's no way a client is going to follow. So the end result was that they completely shot themselves in the foot. Not enough servers on release day meant a lot of pissed off gamers. The game wasn't great, and tons of functionality had been removed from previous versions. (Hell, the menus were optimized for a console, with no back button because they figured you'd have a red "X" to hit.) You need a GameSpy ID to log in, and at first, the only way to ban people was by GameSpy ID, which you could generate in-game. So essentially there was no banning function until the first patch.
If you're a long-time fan of the UT franchise, be glad you skipped this one. It took everything good about the game, and trashed it. (Hell, I tried to pick up my mapping, which was passable under UT2k4. I had to read a huge web page, and spend an hour tinkering about to make fog in a test level. UT2k4 had a fog volume. You made a volume, and checked off "fog". UT3 has dynamically scripted effects. Like fog. They even took the editor and made it so that it was so ridiculously complicated that nobody could casually make maps. Either you need to spend a few months learning it, or you can't do much of anything with it. Sure, it's more powerful than all the previous versions. But it's another barrier for the community. Because of this, there are orders of magnitude less maps for UT3 than there were this far into the life of any of the other versions.)