Although details of Snow Leopard have been hard to come by, thanks to the NDA signed by developers, a French site has posted a screenshot of Snow Leopard's system requirements. The big news here is that 10.6 will indeed require an Intel processor, as rumors had suggested, but also that it will not require a 64-bit processor.
Steve Jobs didn't give much of an introduction to the upcoming Snow Leopard release of OS X during the keynote, deferring to Bertrand Serlet to do the honors later in the day. Unfortunately, the content of Serlet's session is covered by an NDA, so details of Snow Leopard have been hard to come by. Apple has announced a few features, and developers generally like it, but a few of the big questions remain unanswered. French site LogicielMac has posted a screenshot of Snow Leopard's system requirements, thereby answering two processor-related questions at once.
The bad news is that the rumor that Snow Leopard will drop PowerPC support is true. An Intel processor is listed as one of the system requirements. According to some quick web searching, this means that anyone with a Mac purchased before 2006 will be out of luck. This will undoubtedly make a few people upset, since Apple seems to be dropping support for the platform more quickly than it has dropped other processors in the past.
There is some good news here, though. Although the requirements mention Intel processors, Snow Leopard doesn't seem to require a 64-bit Intel processor, owners of first-generation Intel Macs will be able to take advantage of most of the new features. In my mind, keeping 32-bit support is a good move for Apple, since making Snow Leopard require a 64-bit processor would obsolete a fair number of 2006 purchases. It's possible that the requirements will change, since the ones listed are only for the developer preview, but for right now it looks like the Snow Leopard requirements won't be as bad as the rumors suggested.