Well, I'm definitely warming up to the Elemental Army concept now.
Normally I wouldn't participate in a thread like this but Zam, imo, has certainly earned the right to an official response.
The first key concept here is "Fungible". It's an ongoing issue in digital distribution. How many NET new sales would being on Steam provide? That is, how many sales of Elemental would occur that wouldn't occur otherwise.
Starcraft 2, for instance, is not on Steam and I don't think anyone worries about its sales. Sins wasn't on Steam and it sold a gazillion copies. I think you'd be hard pressed to find a TBS (other than the Civ series) that has outsold Galactic Civilizations II (and I'm privy to the numbers on most of them).
When a game is sold on Steam, you lose about 30% to Steam. That's their cut. So just to break even, you'd first have to demonstrate that being on Steam would generate 30% more sales than we would otherwise get and that would be a very tough case to make.
Consumers on the Internet tend to vastly over-estimate the popularity of digital distribution (Steam, Impulse, GG, GOG, D2D, Real, etc.). We often can't imagine why people would go to a store and buy a box. But they do. Depending on the publisher, anywhere between 70% to 90% of their revenue comes from brick and mortar retail stores.
None of these DD services do huge numbers yet. They will, in time. But they don't yet.
But for the sake of argument, let's say that it would be more profitable in the short-term to put Elemental on Steam and the others. I'd even argue that that would probably be the case when you add in GamersGate (which sells well to our demographic) and D2D.
Then the question is, how much are you guys willing to sacrifice for that? Do any of you remember how many updates we do to our games when they're new? GalCiv had like 5 updates in the first month. Not bug fixes mind you but new stuff. Sins of a Solar Empire had several in its first few months. I can tell you right now, Elemental will likely get at least a DOZEN updates in its first 6 months out. You guys have great ideas and frankly, I want them in there. If not now, then asap.
Do you seriously think that kind of rapid updating is possible if you're using a third party DD source?
But let's say that even that's not an issue, then there's the long term issue - a virtual monopoly. Valve is a good company. They're honest. They're hard working. They produce great games. So is Microsoft, incidentally. But once someone establishes total domination, it's very very hard to undo it.
Steam's cut is ~30% today. Maybe they'll need to raise it to 40%. Right now, they can't because there's an alternative - Impulse. Maybe they should start requiring games to include "Steam Achievements" if they want to be on Steam. Of course, that means everyone would have to have Steam running. But right now, they can't require that because publishers can still choose Impulse and the upcoming Impulse::Reactor as an alternative.
Take a few steps back and look at your games. Seriously. Consider this: When was the last time you saw a major NEW title come out. Not a sequel. Not a remake of a classic game as a FPS. I mean a brand new, IP with a big budget. FOR THE PC. It's increasingly rare. It still happens of course but not often. Don't you wonder why that is? Because it's hard to make a profit doing that.
IF Elemental had to give up 30% of its revenue to anyone on digital distribution, there'd be no Elemental in the first place. A turn based fantasy strategy game in 2010 with no roman numeral after its name? Are you insane? But WE can try crazy stuff (see The Political Machine) because we have that 30% "bonus" on our titles. Take that away and we're stuck pitching Atari to do Star Control V as a GTA in space -- for the PS3/Xbox.