WPF and Apple's Core Animation - A resurgence of the desktop experience
What really blew my mind was Core Animation, Quartz Composer, Core Image, and Cocoa's integration of Core Animation (all of this is public info, please don't shoot me Apple!). As a .NET developer, I couldn't help but mentally compare that suite of APIs and functionality with Microsoft's Windows Presentation Foundation (WPF). I'll save the item-by-item comparison for when Leopard becomes public and I can get into nitty-gritty detail.
I can't wait to see what he has to say when everything is released. I talked a bit about Core Animation and Quicktime last year and since then have realized that my assumptions were off base. But there does seem to be a renewed interest in desktop development, and I'm not entirely sure why.
I think mainly it is due to the fact that experience is becoming VERY important, and for experience, nothing is as rich as the desktop. I think that means Apollo is coming in at the perfect time and with a perfect set of features. I also think it means that web developers are going to have the "experience ante" upped on them and they will need to compete by finding richer platforms for their applications. Flash is positionedpositionted to become even more used in the web applicaton space than it is now (especially as Flex grows) and "WPF/E" could come to the market just as the need is rising.