The Gf2MX and GF3 boards are basically the same as the Apple ones. nVidia built these cards with the Mac in mind. Also, Apple just buys the cards from nVidia and sells them at their own prices($499 BLEH!). nVidia is displeased maybe because they want Apple to make more money and buy more of their cards.
And the magic is not really in the drivers. The bios on the GF3 is set for PC when you buy a PC Gf3. To turn it into a Mac GF3, you must get the Mac GF3 ROM from the Apple card, and flash that ROM on a PC GF3. THEN you have to install the drivers. It's really a quite simple process.
I think that's right...check the xlr8yourmac forums for all the dirt.