i tried the new drivers on my ubuntu gutsy machine.
I blacklisted ubuntu driver and tested..they don't work, or better DRI doesn't work with them.
Then i completely uninstalled ubuntu restricted package, and tried again, same result
with those drivers DRI doesn't work..
...well if you were wanting help...you'd have to give us a bit more than just that...like the xorg log, fglrxinfo, glxinfo output for starters...and if glxgears works, fps of glxgears, etc...