We knew PhysX support was due for GeForce 8 and 9 series cards via a driver update eventually, but according to HotHardware we'll finally begin seeing the fruits of Nvidia's February 2008 acquisition of Ageia when ForceWare 177.39 drivers ship alongside the GeForce 9800 GTX+ in July.
Only the newer 9800GTX, 9800GTX+, GTX 260 and 280 cards will get GPU-accelerated PhysX capabilities with 177.39, though full support for 8 and 9 series cards is expected to gradually roll out. HotHardware's preliminary benchmarks using the UT3 PhysX map pack show some serious GPU performance gains for PhysX operations. How this will translate to real world gaming remains to be seen but it certainly looks promising.