Billy "peaches" Wilson has posted a 3 question interview with none other than John Carmack. The interview deals with post-Quake 3 topics, including the state of "Trinity," and upcoming graphics technologies. I found this quote particularly interesting:

Graeme is laying groundwork for our next game now, but nothing is solid yet. He is currently thinking about things with a stronger single player focus, but if Q3:A flies off store shelves, we will probably continue with similar products. There is definitely some appeal to doing a game that can let the Q3 engine show off its graphics power better. In our current focus for fast action, we aren't exploiting all the lush graphics possibilities.