I've already done some research, but Google has been giving me diminishing returns, so I thought it might be more efficient just to ask. As you know, Apple markets Leopard as a 64-bit operating system. It also advertises full compatibility with existing 32-bit drivers and applications "with no emulation". Application compatibility seems to be done by simply having two versions of every library (well, more like four, because of PowerPC). So what about driver compatibility? Well, at little research has indicated that the kernel itself is still 32-bit, in order to maintain compatibility with 32-bit drivers. That's all good and well. But... How the heck would it run 64-bit drivers?! Could someone explain to me whether 64-bit drivers run, and how this is accomplished?