I have something serious to say:
When are we going to start fighting each other? When will tournament start? Because I'm not even thinking about not using on-line awesomeness of this game!

There have been talks on these boards about setting up various multi-player games for a while now.
Time-Zone permitting, I'll join in the fray against my fellow GOG citizens.

It will be nice if GoG open multiplayer section servers of the game they sold...
There will be more potential for some more multiplayer axed games...

With enough players, the servers will take care of themselves. So buy this, damn you! I've got a hankerin' for some good old fashioned fraggin'.
Seriously though, as Multiplayer (or even singleplayer) FPS games go, this one is my all time favourite. It's not the one I was best at, but it's the one I liked the most. I was once fifth in Europe in Q3A, and had the dubious honor of being gibbed repeatedly by Fatality, (insert 1337 way of typing if you must, I despised that back then and still do) as a "reward".
In UT, I never got anywhere near those lofty heights, but I still played the hell out of the game. I played offline and online, and I kept playing long after it went out of fashion. Why? Well, it introduced something that was almost non-existant in other games of the genre. Tactical combat combined with beautiful and mesmerizing level design, dualmode weapons and fantastic soundtrack.
The gameplay itself included so many different arena styles it blew my mind away, while still keeping the twitch action that served me so incredibly well in Q3A. Basically, it had all the components of an Epic game. (Pun intended, so sue me...)
I am going to buy this later, and play it ad nauseum. Right now I got a WoW expansion and a high-end raiding guild to manage, so I can't really take the time. In a month or so? I will stand tall as the Champion of the Liandri Tournament...

While waiting, you can also try "Operation Na Pali". Best Singleplayer-Mod for Unreal Tournament! One of the best singleplayer mods for shooters in general. Way, way better than the official addon for Unreal, "Return to Na Pali". Mapping and coding creativity at its best!