DOOM3; crappy 3-4 players DM. The netcode may suck.Even if they lift the netcode straight out of the Q3 engine it'll still be the best netcode around.
Not a chance in Hell that the netcode could suck.
3-4 Players doesn't sound alot but with those shadows all over the place and the ability to shoot out the lights etc.
The atmosphere hunting down other people and being hunted is gonna be completely new and so much more real.
HL2 trailers are good, the physics engine is really being put to a lot of use in the gameplay demo ( still think shooting the barrels(they always blow up

) would be better then trying to figure out what to shoot to make that iron bar swing ). The girl in the teaser trailer as a nice smile but from a distance the model looks very lo-poly ( either that or she needs to work on her curves a bit

).