I briefly had a G3 iBook before I got my Macbook. That thing was at least 4 years old when I got it, but it still felt solid. It didn't close as tightly as it once must have, and it looked scuffed in parts on the outside, but overall, it felt like a solid machine, and I was all the more impressed that it had survived long enough for me to buy it secondhand (it was a G3 800mhz cd-rom, so it had to have been manufactured in 2003), and still use it without durability qualms. I used it as my sole computer, and besides the slowness (it couldn't play most videos without jerking in VLC), it was a stable, well-constructed machine.
In contrast, I can't help but feel my Macbook isn't going to last as long. There's no question that it's a much more aesthetically pleasing machine, but my preferred metaphor for Apple products - pieces of china priced like diamonds - seems to hold more true with each generation of computer they release. There's no question that a 3 or 4 year old computer can be used to do most of the things most people do with their computers today - surfing the net, checking mail, word processing - but I do doubt most Macbooks and Pros will still be going 4 years from when their original owners bought them. They just don't seem that durable; they seem more like machines designed to last for a year or two, by when the owner will have been convinced (by Apple) s/he needs a faster, newer, sleeker machine that isn't falling apart at the seams.
