Here's an interesting fact - UT2004 is actually still doing pretty well, and would be doing better if UT3 hadn't come along and sucked out half of the community. In fact I think UT2004 has more players than now than it did two years ago, despite the fact that more new games have been released.
UT doesn't attract that many new players all the time, but the ones that get into it tend to stick with it. It's always been the kind of game that sucks players in with its astounding depth. Epic should capitalize on this, rather than shoot themselves in the foot repeatedly by releasing a new UT every three years or so to try and drum up more sales and splitting the community into 50 different pieces.
I know this is a radical idea coming from a community member, and most people are opposed to it on the grounds that it looks like a profiteering move, but I think the best thing Epic could do to save UT3's community would be to add some stuff, change some stuff, fix a lot of stuff, and re-release it next year a la UT2003 -> UT2004.
Also, I know conventional logic says that catering to the competitive community is a poor investment economically, but I think games, especially FPS's, have reached a stage where knowledge of their being played competitively is so widespread that Epic could really have some success exploiting this avenue. There are so many great features they could build into the game to help this:
1. Real community tools, including support for clans and ladders, either hosted on an official website or built into the game.
2. Official tournaments and events.
3. Promotion, shoutcasting, and UTV'ing (anybody remember this awesome mod?) of events, again all integrated into the in-game community tools.
4. Decent demorec support so that the community video makers can do their job promoting the game virally. An official video competition of some kind could be good too.
5. CONTINUE TO SUPPORT THE GAME for competitive play and seek revenue that way, rather than focusing only on the retail sales and releasing a totally different UT game in another 3 years and starting the whole cycle all over again.
I know that after past experiences this sounds like crazy talk, but if they did it right, it could work. I see this as the only viable option UT3 really has to find its niche in the market right now, because it's an aspect that's being totally neglected right now on PC and PS3.
I've already gotten my $50 worth out of UT3 and I'd be happy to shell out again next year if it meant getting a truly fixed game. It would give the title a chance to have the good launch that it miffed so badly, and Epic would at least get a little more money out of it to justify the cost of making the major, MAJOR fixes that the game needs.