The full teardown is here. Good news is that, as long as you're willing to swallow hard and pull that glass front off, swapping out the hard drive looks trivial compared to the current generation.
Heh. The old "I'm a PC, I'm a Mac" ads have been tired for a while, but they've come up with just the right one-two combo for the Windows 7 launch.
http://www.youtube.com/watch?v=AiU1Gu14xG0