I guess when it comes to hardware, it's maybe okay for an iphone to crap out after a few months of usage since this is normal for pretty much all cell phones. Has more serious business-person stuff like the blackberry tended to last longer? I don't know. But if it has that doesn't matter since the iphone's main customer base is the clueless consumer.
As for computers, historically on average Apple computers have had useful lifetimes much much greater than PCs.
Currently, the Average Mac desktop and laptop costs $1000 more than the average PC desktop and laptop, but consumers on average replace PCs so much more often that it's kind of a wash.
Windows XP pro seems to work okay in my experience... It's pretty crappy overall, but at least it's kind of a consistent and stable sort of crappy. *evidence of criminal activity removed on the advice of my lawyer* What the hell am I supposed to do with those? And what do I do when I run out of space to bury the bodies that I already have collected in barrels? I've never used Vista, but I understand that it was total crap, compared to XP.