You say "mindless shooter" like it's a bad thing.

From the screenshots and video I've seen, Doom 3 looks much better.
Your mileage evidently varies.

Half-Life's success has no bearing on this game. Unreal was a fun game. Unreal 2 was pretty, but it sucked. Half-life's mutliplayer was broken out of the box. Who knows how well HL2 will do with the mod community? HL was easy to work with. HL2 is a big question mark until it hits the street.

And Id's games have a ton of staying power. HL was embraced by the mod community. Id *created* the mod community.

Finally, many dozens of games have been built from id-licensed engines. Longevity is where you look for it.

So yeah, HL2 seems to make past and present games look archaic, but I don't expect it to be alone on top of the hill graphically.