Off the top of my head, if I wanted to spread the news as far and wide as possible, I'd post in a whole bunch of forums. The forums for, say, Introversion, Cactus and Penny Arcade would have an indie audience. The problem, of course, would be that if you sign up to post your game on there, people might get annoyed. Still, if you did it nicely they might not be too hostile.
Could you also email gamasutra about your game? Every week they have a roundup of the best indie games. Though, it might make more sense to contact indiegames.com, which is gamasutra's sister-site (if that's the right term) focussing on indie games.
Secretary of Unknowable Knowledge for the Rock/Dink administration '08