Snow Leopard has been reviewed by everybody at this point, but one thing the Engadget review is that with 
Snow Leopard, OS X is now 100% a 64-bit operating system. Woo! In addition to to getting Apple into the 64-bit age, this latest revision to the OS X operating system completely moves the Mac platform from the old IBM PowerPC model to the new Intel chips – Snow Leopard will not install on a PowerPC machine.
But again, the more important part in my mind is the 64-bit side of things. Any regular TG reader knows that I love 64-bit. That said, there is a story making its rounds that 32-bit machines aren’t actually limited to 4 GB of memory. Now I’m not a computer engineer, but from what I had read, 32-bit operating environments just have a limited number of pathways (2^32 = 4.29 x 10^9, which is about four gigs of meory). If anyone reading this knows something, please tell me. 64-bit is better at doing certain types of math, but if there aren’t memory limitations, then 32-bit operating environments are potentially not all that important bottlenecks.
