During the post-show interview, Marty Stratton described id Tech 6 as a significant departure from 5. From what I can see, the new Doom is not using megatextures. I don't get any impression of the painterly quality of megatextures in the demo. Instead, I notice a lot of atmospheric effects and lighting.
I'm very disappointed by this. I'm a big fan of id Tech 5 and enjoyed immensely the games made with it (RAGE, Wolfenstein, and Evil Within). The amazing detail the engine allows breathes so much life and character into its worlds. I find games like Crysis 3, with all its bells and whistles, to be quite dull by comparison. I was hoping they would continue to iterate on this technology, which seemed to get better (less pop-in, fewer blurry textures) with each game using it.