Frankly, even though I don't typically use the fglrx drivers, I am disappointed in this move. For example, at the present moment doom3 is only playable with the arb render path with the open souce drivers and, even then, the performance is horrible compared to fglrx. quake4 is unplayable with the open source drivers due to a lack of support for decompressing s3tc textures on the card. libtxc_dxtn is available ( http://homepage.hispeed.ch/rscheideg...3tc_index.html ) but has issues with multitexturing on the r300 driver and makes nearly every texture in the game flicker. ut2004 also gains a huge speedboost from that library, but experiences the same problem.
While I have no problems with AMD creating a legacy driver package that gets updated to support new servers and kernels, I think it's quite foolish to stop supporting them in the binary drivers altogether. Any users of those games on r300-r500 hardware (which are perfectly capable of playing those games on fglrx with good quality and performance) will be left in the cold when it comes time to upgrade their X server or kernel.
Once those items get ironed out in the open source drivers, and the remaining issues such as power-management get resolved, I'm all for dropping the from catalyst.