Nouveau is an awesome project, but for later cards it's basically a dead project. You can get some features to work, but without proper power management there's no justifiable reason to daily-drive it. The proprietary driver is by no means perfect (particularly for Wayland) but it's the only real option if you own a modern card.
> And Linux is not even on the radar for Apple. :)
They must be awfully curious about why Xserve failed, then.