Found an interesting story over at IMG about Adam Thayer, who is unofficially developing drivers for the Voodoo 3, 4, and 5 cards under Mac OS X. Since 3dfx went out of business last year, there haven't been any updates to the drivers at all, which means that Voodoo cards do not accelerate OS X. Thayer is trying to remedy this unfortunate situation by first creating functional drivers for the Voodoo3 and then move on to the other cards. After this, he plans on achieving OpenGL support with his drivers.
Keep an eye out at Thayer's website for updates; this should be very interesting to watch unfold.
The importance of this is that Myth III will be soon released as a Carbonized application and it is believed that the OS X version will run superior to the OS 9 version. Options for Voodoo3-owning Mac users are getting a new video card or rebooting into OS 9 every time they want to play Myth III. However, if these drivers are successful in their aims, Voodoo cards will be functional under OS X and users will be able to play Myth III just fine without any additional steps other than launching the application.