>One nice thing about Ubuntu still being based on Debian is that it's easy to install enough to satisfy Steam and all the games, since Ubuntu is what they target, while leaving the Ubuntu UI off and doing whatever you want underneath.
On my Arch system, Steam works perfectly well for me.
Even in Ubuntu 13.04, Steam installs a bunch of Ubuntu 12.04 stuff instead of relying on native libraries. So the Debian base doesn't matter much for compatibility. It's more a matter of packaging it with everything it needs to run on any distro.
I've gone deep down that hole. XMonad, fairly custom, custom keyboard layout, custom emacs... occasional light gaming is all I do now that Windows has an advantage for me personally. YMMV.
One nice thing about Ubuntu still being based on Debian is that it's easy to install enough to satisfy Steam and all the games, since Ubuntu is what they target, while leaving the Ubuntu UI off and doing whatever you want underneath.