Nvidia blob does modesetting in the kernel. They don't need to tie into the kernel modesetting code, since they do all the modesetting in kernel space inside their proprietary blob already.In particular, Wayland requires KMS support from drivers, which NVidia can't implement due to it requiring GPL-only symbols in the kernel.
You don't really need DRI2 and GEM, but the infrastructure needed for redirected direct rendering, which Nvidia has had for a long time.It also assumes the use of DRI2 and GEM, meaning a major redesign of NVidia's driver would be needed and they wouldn't be share nearly as much code with the Windows driver as they currently do.
KMS, DRI2, GEM, etc. are open-source technologies which pretty much do the same thing that the binary blob does internally. Nvidia just can't be bothered at this time.
Linus also started Linux in order to learn about kernel programming.
The exact opposite reasoning than relying on black box blobs for a few FPS and HD video.
Don't be so selective with your arguments
OK, in that sense it is technical (currently hard-coded to use DRI2), but there is no reason why this could not be rewritten to use nvidia's stuff providing equivalent functionality.
The main question is whether there is qa wish to do this, both from the Wayland developers (currently firmly in the open driver camp and funded by Intel) and the nvidia developers (no interest in Wayland at the moment).
If Wayland becomes relevant, nvidia will release something for it, no doubt.
http://www.anandtech.com/show/2745/23 which concludes
Anyway, that's comparing a single card rather than the generation as a whole, which is what i meant originally.If you've got a 30" display then either card will work, it's just up to your preference and the items we talked about earlier. If you've got a 24" or smaller display (1920x1200 or below), then the Radeon HD 4890 is the card for you.