This is the most retarded thing I have heard from Apple. To use the 64-bit Kernel in Snow Leopard you have to hold down the "6" and "4" key during boot. otherwise it defaults to the 32-bit kernel.
64-bit Snow Leopard defaults to 32-bit kernel | Apple - CNET News At least with Windows when you install the 64-bit OS you actually get a 64-bit OS. Same with *NIX.