I got my copy of Civilization 4 in the mail today, which was exciting. However, I've fallen victim to one of the traps of early-adoption. As most of the Amazon reviews have pointed out, this game is enormously resource-intensive. And for no good reason as far as I can tell. The graphics are nice, but hardly mind-boggling. I've seen games do a lot more. I suspect that the port was rushed, and hope that future patches give it some boosts in performance.

Update: for anyone else wrestling with this, the fanatics forums may be helpful.