I assumed by "So here it's tri-flat being render using a shiny compiler infrastructure." [http://jglisse.livejournal.com/] that it could do some trivial demos with r7xx. My mistake then.
There is a commit in git which turns off all rendering, perhaps it was on at the time of the blogpost.
Good news is that log evidence at http://cgit.freedesktop.org/mesa/mesa/log/ indicates that 600g is moving forward. It'll probably be months before it's usable, though. I recomend xorg-server 1.8.0 (NOT 1.8.1, which crashes) and mesa 7.8.1 in the meanwhile, it's stable and works great with r600.