Luc's proposal involves reorganizing the kernel DRM, separating out the various parts of the DRM, moving out driver-specific code from libdrm, splitting out the mode-setting / memory management components, and to modularize Mesa and provide a formal API for this graphics stack. Luc has done a proof of concept for this new unified tree design using his VIA xf86-video-unichrome driver and encourages other X.Org developers to do the same. Luc didn't expect this talk to be received positively by all developers that were there in Brussels, and that certainly was not the case.
Click here to listen to the hour long MP3 of Luc's unified graphics tree talk. It's complete with the heated Q&A from Intel's Eric Anholt and others. Afterwards the polarized debate and discussion spilled into our forums. Luc's slides that go along with the audio can be found in this Phoronix article.