Games of 2004

Civilization 4 perhaps? I'd like an integration between the civ and alpha centauri technologies into one, mutli-world based strategy game.

I've actually only played Civ 2, and I loved it. I hear Civ 3 is a lot more in depth and tougher, but I've yet to get around to purchasing it. If Civ 4 is coming out soon though, I'll probably just hold off until that hits the market.