One thing I haven't liked from the vids of HL2 and Doom 3 is the lack of vehicles. The following is a quote from a recent interview with Carmack:
Even if you don't agree that Doom 3 will be great, you gotta know there will be some good games come out of the engine. I'm VERY happy to see that he is including vehicle support. I think BF1942 has set a new standard in FPS and hope to see more like it. I can only imagine what BF1942 would look like in a Doom 3 or HL2 engine. :shock:
We've got some neat things where you can control some big machines and do some cool stuff, but it is still a 'running a person around, shooting at things in the world' game, and I didn't want to make it anything other than that. We have vehicle code in there that I know Splash Damage is playing with and making buggies and stuff fly around, but I'm most mistrustful of adding that sort of thing.