Well, I'm a bit late on this update due to a variety of reasons.

I managed to replace the hard drive in my wife's iBook over the holidays using the directions which I linked in a previous post. Disassembly and reassembly was quite a bit easier than I expected it to be - so easy in fact that I did it twice after realizing that I had forgot to put the little bar that holds the hard drive in on the first try (!). Having all of the tools laid out beforehand, and a bunch of little baggies to hold parts simplified the process - it really is about 2 hours to replace the drive assuming you only have to do it once.