i was fortunate enough to be among those invited to epic to check out the engine and play the game for myself, at epic.
to the guy who's playing the leaked version: the game runs beautifully, and further optimizations were present in the build i played. this is why you dont touch the leaked stuff.
anyhow, as far as the -game- is concerned: absolutely drop-dead gorgeous environments with a real push in raw polygon counts. the gameplay on the other hand has beefed up deathmatch, domination, etc. etc. and yet Assault is no longer a game mode (which was my favorite from UT). i'll be buying the game for the incredible art assets (kudos to shane caudle; brilliant work on the engine tech demo stuff--and he let me play on his computer) and, you guessed it, the engine.
the engine really will be the one to beat for a while, in terms of overall flexibility and mod friendliness. i've been a total quake head, and trying to put my player models into UT was a headache. but the extreme gains in terms of feature sets, _tool integration_ and overall flexibility are absolutely tremendous. yes, doom 3 is arguably better looking given it's emphasis on realistic shadowing, but id's support of modders often strikes me as incidental at best sometimes. their artwork development pipeline is custom tailored to their artists and doom3 can only handle a certain range of environments; ut2k3 is not as realistic but far more robust (beautiful terrain generation stuff) and because of so many licensees it's probably going to be one of the easiest engines to get custom content into.
the new unrealed is superb; a better particle effects engine than you could ever actually utilize, terrain generation is a snap, importing new models is streamlined as well. custom tools for animation and scripting, etc. built into unrealed, not to mention one to edit cutscenes.. oh, and you can preview it all (including cutscenes) realtime in the editor. oh, and a shader system, etc. etc.
i could go on, but i dont want to come off as a total plant
the point is, i'm not real excited about the game itself per se, but this engine is beyond words. i expect some really great user content to come.