While it wouldn’t ever anger me, it does confuse me a bit. The Steam runtime is supposed to act as an abstraction layer between the game and the underlying distro. If it does its job, it shouldn’t matter with distro you run.
Most games released after the Steam beta don’t list 12.04 as a requirement anymore and Super Meat Boy gets it right:
OS: If you’re running the Steam client, you’re good
Or Dust gets really specific:
The only thing that would make a difference is the GPU driver shipped with the distro, but I’m guessing you’re running with the latest stable NVidia driver, right?
Also, what’s so minimal about dual GTX 770 with an octo-core CPU ? Shouldn’t Pedro be the one to run Ubuntu 12.04 if one has to ?