The Steam version will have different keys, so I think we will all get keys soon if we bought the game before steam release.
It might come on Steam, but here's what Kivlov said about it:
Kivlov wrote:
We don't know when we will be able to release the game in STEAM yet. There're a lot of bureaucratic things to do. It's rather difficult and take for a long time as we're not the USA resident. This situtation doesn't depend on us unfortunately. Now everything we can do is to wait...