It would be very nice to see all those "yes, I would buy it" votes convert to sales, seeing that there are over 15000 of them already. Currently ranked #43.
Its a catch 22.
A lot of people won't pre-order because it isn't on steam. Its not on steam because people don't know about it/ haven't bought it yet.
I think if the pre-orders went through the roof, steam would allow it. I've seen them do something like that before, if the game has been sold elsewhere usually they allow it through.
Anyways: As soon as you guys get on steam offer up an Early Access or something.. Release the Alpha build people will buy it up.
Or make it very clear that you will get a steam key when it comes out on Steam. A lot of people are waiting on that too.
Also: New screenshots.. progress on the Alpha, new videos of new game footage. I know the sneak peak is going to be pretty big and I would guess you are waiting for those pre-orders.. but even new screen shots of in game footage would drum up a lot of interest. (we like shiny stuff)
I want to point out that you guys posting in the steam, answer questions, and on here is a big deal. Huge Deal. More of that and people will see that you guys are very serious.
Too many devs, more so indy devs just throw the game out and get their cash and run away.. Its so nice to see devs around, commenting on forums.