Unigine's OilRush game has been available for pre-order for a few weeks now (which also grants users access to betas of this real-time strategy game until its June launch), but to date they've sold less than 1,200 copies. Fortunately, there's two major changes to be announced very soon...
Needing to buy the game for each platform was the biggest complaint here on the forums last week. With that complaint resolved, let's hope that people start purchasing instead of finding other reasons to complain.
FWIW I'm planning to buy a Linux copy of Oil Rush once my new graphics card is delivered and setup.
As much as I appreciate AMD's open source driver efforts, no open source driver will run Oil Rush (due, I believe, primarily to mesa limitations), and since I'm using a non-Ubuntu and non-Enterprise distro (Arch) I've given up on the Catalyst drivers. So at moment I cannot run Oil Rush. I've had to get an Nvidia card for my Linux gaming fix.
Kudos on the push to Steam, Unigine guys! And the cross platform version distribution was definitely the way to go so far as political will is concerned. I just hope you keep making the right noises and doing the right things. Don't be Epic Software and we'll love you for it.