It's such a pain in the butt to change out the old drivers and software changes for my ATI TV Tuner, Remote Control & my 9600 that I might wait until they stop making the updates. (Maybe)
http://www.techimo.com/newsapp/index.pl?photo=9872
If ya read the news you would have known days ago
So far I haven't had too much time to test out the 4.2 drivers, but they work great here on a radeon 9000 pro. I actually never had a problem with the 3.7, 3.8, 3.9, 3.10, 4.1, 4.2, they all work here smoothly and that is all i care about.
It does look like there were a few performance increases but i have yet to try UT2003 or UT2004 demo on it.