Hi,
I have some good news regarding the Steam keys for those who've already purchased or got the game on other stores, namely IndieGameStand, Desura or GamersGate.
IndieGameStand and Desura USC owners (including sales from BundleBandits' Insanity Rush Bundle) can already claim their Steam key on the appropriate pages (IGS: USC game page; Desura: Collection).
Keys to GamersGate are already being sent, it's only a matter of short time; you'll be able to redeem the game before the Final Release arrives. I'll keep you posted.
Please note that while you can already redeem the game on Steam, it won't be available to you for play until the Steam version is released (12 May).
If you encounter any problems during acquiring your key, please reply to this thread or--if you prefer privacy--contact us at [email protected] so we can help sort things out!
Non-Steam versions in the future
As things currently stand, we're also set to continue deployment on other store platforms. Final Release version 1.0 will be available on these at most a few days after the Steam release, as well as all future patches/updates. So whether you claim your Steam key or not, you'll be able to play USC on/from your favorite store platform. Additionally--and naturally--all future purchases on these platforms will include a redeemable Steam key. (Minor details may change, I'll keep you posted.)
Pre-purchase and launch discount
There isn't and won't be a pre-purchase event. We WILL, however, give a LAUNCH DISCOUNT, so if you don't already own the game, we sincerely recommend to wait until it's released, don't buy it on non-Steam stores until then.
Thank you, and happy hunting!