The next NDA-free information dump from AMD will come in the way of tcore, which will help open-source developers on R600 2D acceleration and the basis of the 3D support. In the IRC channel today, it was mentioned that the tcore release will contain about 60,000 lines of code. The RadeonHD driver with 3D support will come in two stages, with the first being a "first cut 3d driver" that is Compiz capable and other basic capabilities. This first-run open-source R500/600 3D driver will be based upon the R300 DRI. The second iteration will be much cleaner, rewritten, and based upon the Gallium3D architecture. AMD's John Bridgman and various X developers had participated in this discussion.
Another interesting discussion happening this weekend is taking place on the Phoronix Forums and is about mixing open and closed-source software. It was brought up whether AMD should drop the development of the fglrx driver and focus their efforts on the RadeonHD driver, followed by developing a binary module on top of RadeonHD for supporting advanced video-playback, etc. Be sure to share your thoughts on the matter in the thread.
If you're interested in more reading, check out our RadeonHD articles and forum discussions.