All we need now is radiosity lighting with real time moving lights/objects, which Doom3 does not have. So Doom3's lighting is still not "true" lighting yet, but it's a step closer. It's interesting to realize that quake3 has 1 lighting advantage that doom3 does not have, BSP compilers calculated radiosity for the final product map, but of course doom3 has so many other lighting advantages that outweigh quake3's. It's not John Carmack's fault that we dont have radiosity in Doom3, it's simply that CPUs/GPUs are not powerful enough to compute radiosity in real time with moving objects yet. Were basically waiting for nVidia and ATI to get graphics cards out that can handle it.
This link below shows you guys what the future of Carmack's engines will do, that Doom3 does not do. Doom3's engine is the pictures that say "No radiosity" on it, future engines will be the ones with radiosity included.
http://www.students.tut.fi/~warp/pics/Radiosity_test2/
The last example is my favorite one, the flashlight is shining at the corner of the ceiling, no radiosity shows complete blackness behind the flashlight, with radiosity included, light reflects off of surfaces (the ceiling corner) and bounces around (like real life light physics). Light reflects off of light colored surfaces (white), and gets absorbed by darker colored surfaces (black). So how much light reflects depends on the diffuse surface.
I’d also like to note that radiosity lighting generally makes environments “brighter” and more “real life”, probably one of the reasons they chose to make a single player doom game with the doom3 engine and not multiplayer, is that the engine suits it best. It makes things more darker, gloomier, doomish, etc.. Since things will be darker, a multiplayer deathmatch engine will probably have to wait till radiosity lighting will be included with Carmack’s engines (so brighter environments for concentration on fragging, like quake3). Maybe we will se it for the quake4 engine.
Other radiosity comparison links:
http://www.students.tut.fi/~warp/pics/Radiosity_test/
http://o.ffrench.free.fr/graph/radiosity/
http://www.google.com/search?q=Radiosity (just look around, you’ll find tons of stuff on it)