Check this out. Mac OSX Leopard, which will be available "Spring 2007," has a feature called "Spaces." The idea is quite a simple one, namely having several desktops, each with its own windows running, on one computer, and switching in some way. The idea, however, has been around for years and has been implemented on all the major Linux window managers for years. Fluxbox also offers tabbed windows in addition to virtual workspaces.
So much for "new" and "innovative." Still, Apple seems to be far ahead of Microsoft on this one, no surprise there. Maybe someday Mac OS [insert appropriate number] will actually be a serious competitor with Linux. But if they want to start coming up with stuff before us, they're going to have to be much more open source. Now that would be "reaching enlightenment" as this page so modestly puts it.