If you’re curious about Leopard, and haven’t had a chance to pop over to see Apple’s OS Foundations overview, I recommend you try to find a few minutes to browse through it. It’s part 6 of Apple’s Leopard Tech developer series and it’s freely available to all comers–you don’t have to be a developer to access it.
Better Security is great, but what happens to the "Mandatory Access Control" and "Code Signing"? Why they are gone?