Mixed bag. It's much closer to the first game, albeit a bit slower, and slightly clunky-feeling. Graphics hold up well thanks to the engine, but it's never been a pretty game because everything's blanketted in blurry bloom lighting - it looks like you're playing through foggy glasses.
If you like the first game then you should enjoy it, but it'll never live up to the nostalgia (particularly because the level design, music and world building give it just a fraction of UT1's incredible atmosphere).
If you're more a fan of UT2004, you may not like it at all, because it has almost none of the trick jumps or defensive play. It's very much a game where you die in an instant, unless you're quicker on the draw. Dodge-jumping's out, you can only double-jump and wall-dodge. Assault's out (earning the game my immediate hatred), but Onslaught gets an update, and all the vehicles are still in, plus a few more. Level design (from a pure gameplay standpoint at least) is a notch above UT2004's in my opinion.
It also has a slightly horrific attempt at storytelling in single-player - the campaign is structured around a story (presumably written by 10 year olds) rather than a tournament ladder.
