Mine is over 4 years old. Never had a problem until last week when I dropped it on a cement staircase and took out the backlight bulb.... a plastic laptop would have exploded... It fell about 6 feet. It still works fine. I just have it plugged in to an external screen.
My friend is going to fix the screen for a lovely $30 cause it just needs a new bulb.
Anyway, I've never had a problem. Have upgraded through 3 OS's. Never had a virus. Computer is massively speedy. I can run and always have been able to run Illustrator, photoshop. and flash at the same time.
And.... my laptop still sells for around $500 on ebay. And it is over 4 years old.
My friend sold his perfectly good 6 year old powerbook a few months ago for $300.
There is nothing wrong with Buying a PC. It is just that a lot of people who have mac products have noticed that they last a long long time with out problems.
I'm still using the 1st gen 1phone as well.... Works awesome.