3dfx announced details about Mac versions of Voodoo 4 and Voodoo 5 PCI cards.
Both of these cards will be both 2d & 3d cards and support the major 3d API's. This will help keep the Mac Gaming experience on par with the PC.
Unofficial Voodoo 3 Drivers have been available from 3dfx for some time now, and according to this MacCentral article, support for those will continue with an upcoming release shortly.