This is similar to back in March when there was the R500 glxgears milestone and coming two months after that was full 3D support with some Linux games running. However, this open-source code isn't published quite yet.
We're told by John Bridgman that this code will, however, be published in the near future. Alex Deucher may even forgo attending XDS 2008, the X.Org conference taking place next week in Europe, in order to spend the time getting this code ready for publishing.
Coming as soon as next week may be the DRM code for the R600/700 series and a working demo program that can be easily built and submits command packages to the graphics processor. Following the release of this open-source code will be the NDA-free 3D R600/700 documentation.
In achieving today's success, they had used the DRM (Direct Rendering Manager) implementation that will be made available plus this to be released demo program. This triangle program, called r600demo is based open their old r300demo program. The r600demo works just like Mesa in calling DRM, but it's code-base is significantly smaller which makes it a nicer first-step in enabling other open-source developers to begin hacking away at the Mesa code.
While the first bits of code and documentation are coming for the Radeon HD 2000/3000 and 4800 series, it will not be instantly usable to end-users. However, by the end of the year we should see the first-cut support similar to what we saw back in May with the Radeon X1000 series in terms of DRM and Mesa capabilities. It shall be an exciting few months ahead on both the open and closed source fronts.