This news item is coming a bit belated due to LinuxTag, but the DRM graphics driver pull went in last week for the Linux 3.5 kernel. The open-source kernel graphics driver changes this time around are absolutely huge, complete with three new KMS drivers...
All awesome things, but the #1 thing keeping me from using open source graphics stack right now is not really that heavily related to the kernel (AFAIK there is plenty of kernel work to be done, but even more userspace work): RadeonSI
Funny thing is, after my first card under Linux (an Oak OTI-067, which was just an unaccelerated framebuffer...), I used a Cirrus Logic 5429 for a while then a Cirrus Logic 5434 for a good long time. It was amusing to me once I started messing about with VMs, and was showing Cirrus Logic hardware.
Probably a good choice though -- a 5434 supported bitblt (including from off-screen memory to the onscreen framebuffer), line fill, rectangle fill, and hardware cursor, and maybe color depth conversion.. which allowed a lot to be accelerated... and not much else, so there isn't a lot of state making the virtual card complicated to implement.