http://www.extremetech.com/article2/0,3973,1188167,00.asp
We ran the GeForceFX 5900 through 3DMark03, first with the current 44.03 driver, and then with this new 44.67 driver. The performance increases seen in 3DMark03 were substantial, almost double on one of the tests. We also tested three of the games we usually use for 3D testing. We found essentially no performance difference between the two builds there.
Apparently whatever changes were made in 44.67 were directed at addressing the performance and problems we previously uncovered with 3DMark03.