I personally like steam; it's a mild form of copy protection for the publisher and has some community features I like. When you've seen what Ubisoft is capable of, it doesn't matter anymore and makes Steam look like a good product anyway

. (No you can't fight the fact that all new games will need online authentication. The consumer - producer relationship is not as simple as some people here try to make it.)
I can't understand people who say they really liked the game and looked forward to it but now can't buy it because it uses steam. You're not going to get "antidrm-points" for being adamant when you die without having played civ5 and all its sequels. It's just, people who really like the game, will buy it anyway no matter what.
The only thing I dislike is that there won't be a regular collectors edition fir civ5, so I'll probably have to buy a hard copy as well as the digital steam version.