(Pls note my post isn't directed at you personally, just to this very good post).
It's cool. 
Steam as a digital store is great. Similar to Impulse or Gamersgate it gets a lot of love from people who want to buy their game digitally. The problem though which many don't see is that Steam doesn't end there and controls your games. You can give me posts all day long about "offline mode" all you want, but Steam is still there, in the way. A digital store like Impulse I can buy and download the game and uninstall Impulse never to be seen again if I want. And I own the game and can install it 10 yrs from now without Impulse. Can't do that with Steam.
For the record, I'm not a huge Steam fan. I buy games on Impulse over Steam if given the option, pretty well entirely because Impulse games behave like retail games and don't require Impulse running to work (and don't require me to take a cab to the store, since I'm a 30 year old who owns a house but not a car).
But I don't get very worked up over Steamworks. Maybe it's because I'm a developer. I reuse frameworks and APIs whenever I can in my job, because they save me time, expense, and maintenance later. I don't do games, but the premise is the same. Developers look at all the functionality Steamworks offers them *without them having to build it* and see good things. They've got their multiplayer matchmaking, friends, communities, achievements (a selling point for some), and the other stuff Steamworks provides. Looking around, there's nothing else that offers a comparable featureset except GFWL, and everybody hates GFWL.
Given the option of using Steamworks or having the expense of building and maintaining all that myself? It's an absolute no brainer. Even more so considering the cost of building games keeps going up. Reducing costs by using a proven platform is just good business over trying to do all that stuff in-house.
Steam is very much liked by those that play shooters. It's very much a multiplayer platform and the common thing that people post about how much they like Steam is because "they get notified when friends want to play a game" or "they can chat with friends while they play" or whatnot. Basically Xbox for the PC. So if you're a kiddie (no offense, but let's be realistic here with what the audience really is) FPS gamer Steam is great. Steam is awesome. If I was big into multiplayer games I'd probably like Steam too.
The PROBLEM is when you start forcing Steamworks and Steam down the throats of primarily *single player* games, which the Civ franchise is (and Fallout NV which is single player *only* for crying out loud). Steamworks offers *NOTHING* of value to a single player gamer. Achievements? Please. All it does is get in the way and has many downsides which have been listed many times. But the Steam lovers say "but it allows me to know when my friends are on so I can play COD with them". Great, that's awesome. But what does that do for the Civ gamer, the vast majority of which play single player and never go online. Nothing. And *that's* the point.
I've got friends who primarily play single player RPGs on the 360, with over ten thousand achievement points. They're a selling point for a surprising number of people. My wife actually spent time grinding gold in Fable 2 to get some, at least until she started making endless money from houses or something.
My dislike for Steam isn't hate for Valve. I blame 2K and Firaxis for this decision to build it into Civ 5. They are the ones to blame.
I blame Microsoft. Fallout 3 used GFWL for achievements and such. Installing it, I had weird issues with needing to update GFWL with some odd patch that confused Vista, then getting it to sign in, and so on. They wouldn't have switched from that to Steamworks without a reason (and they're not alone, GFWL has almost no developer support anymore).
GFWL should have been the solution for all this, but Microsoft totally screwed it up. Valve came in and offered something better. At the moment, nobody else has a comparable option (Reactor isn't out yet).
Just look at it if you're Firaxis. You want to offer MP, matchmaking, a mod hub, and achievements. You need to keep costs down where you can, because 2k said so, and so much of the game is changing that your developers are already busy. Valve says "we have this platform that does it all, has been proven in dozens of games already, and isn't terribly expensive."
What do you do?