John Carmack gave QuakeCon attendees a glimpse into his thoughts about the next-generation of gaming graphics. id Tech 6, for example, probably won't be coded in Java or any protected language. It also will be designed for hardware that doesn't excist right now. With new discrete graphics players entering the field (Larrabee, Fusion, etc), Carmack knows that the PC space is relavent, and that's where he'll be looking when thinking about coding his next engine.
When considering console technology and the next-generation of consoles (whether it's PS4 or Xbox 720), Carmack actually hopes that the console generation will last twice as long as the previous ones -- though he doesn't think it'll be a reality, as console makers will want to one-up competitors with early releases. Doom 4 will come out for this generation of hardware, but anything after that is up in the air. But one thing he's certain of: the practical approach for people who want to code games that look like today's games but better will be polygon-based.
With CUDA and General Purpose Computing, Carmack says he thinks it's interesting, but he's still waiting to see if there will be other real-application standards to drive graphics. There's no solid background for these new technologies like there was with OpenGL and Direct3D. He sees these technologies as toy research products, and not real applications. It's just like the mid 90s, when graphics were in a period of flux. Billions of dollars are being spent to make bets on the next big thing, but he's worried about years being wasted on speculative architectures.