Via Blackfriars’: Given what we know and have seen of Leopard features such as Time Machine and the new iChat and in existing apps like FrontRow, this would make perfect sense, especially if it were implemented in OpenGL. Applications get their own canvases in a 3D world, and the OS is responsible for keeping those canvases updated and visible in various orientations. One visual 3D imaging model for all apps that the OS manages and keeps sorted. Sweet.
We may see visual effects similar to Beryl or Compiz on Linux. Apple has to come up with something visually striking to compete with Vista.