Next Generation Online has posted the online version of the interview they conducted with John Carmack that was published in the February edition of their print magazine (thanks Hostage). Since it went up (and is dated) yesterday, I don't know why they say it is "on the eve of the release of Quake 3 Test for Mac," but either way the piece contains a load of info, both general stuff, as well as some technically-oriented bits. This question in particular is one I've often pondered myself:

NG: Do you ever see yourself getting bored of game programming?

John: That was a big issue early on at Id. There was a fear that I would be bored and go off to do something weird in operating systems research or something. When Mark Rein was our president, there was actually a discussion about me signing a contract saying I'd stay for a certain amount of time. But it turned out that I've been able to find so many interesting things just in the context of games. Things like all the low-level programming on the consoles, where you're doing everything from the ground up. I retargeted the C compiler to the Jaguar, I've written new linkers, and all the stuff I've learned about networking and different communications things. It's been a lot of fun.