Spent all day fiddling with settings on our Steam panel. Finally got the builds working on Steam - that was a rush! From my developer's account I can now download, install, and play the game from the steam client. That's awesome! Still working on getting the mac build to work.
In doing all this, I found a new way to package the installers. Apparently you can create a "standalone" package that packs in all the Adobe AIR dependencies, so you don't have to run that cheezy installer thingy and worry about whether you have the latest version of Adobe AIR or anything (or bother installing/updating it). I figured this out because Steam prefers if your game can install "silently", ie, without having to prompt the user with any kind of message. So, now, on Mac and Windows, I can deploying a build simply by copying a folder with a bunch of stuff in it, with an executable that you run in the top directory. The only downside to this is that the user can't get the latest security updates to adobe air automatically, but I can always package those in to the next release/patch myself.
I think I'll still keep the regular installer for the main version of the game, but the good news is this means the experience will be better on Steam, and we have an option in our back pocket for players who have trouble with AIR on Mac/Windows.
This sadly won't work on Linux, as it's a feature of Adobe AIR 3.0, and the last supported version on Linux was 2.X something.
I have no idea how/if we're going to deploy the linux installers on Steam, but I'm on some sort of Valve Linux mailing list now so I should get some answers soon.
It looks like nobody's reporting any major problems with the version 1.0.35 build on the test server, so tomorrow I'll push it live.