Also, because Apple completely backs their product, I heartily recommend it to folks who ask me what kind of computer they should buy. Why? Because Apple stores are becoming ubiquitous, and I would much rather said person resolve any issues at the Genius bar than call me at 3:00 in the afternoon with questions about how to add a new email account. I cost waaay too much to be someone's help desk.
Do you pay a premium? Probably. Is it worth it? Undoubtedly. Is this a gamer's dream system? Absolutely not, since it isn't upgradeable. Is this a good machine for someone new to computing? Without a doubt!
Could I buy a similar system from Dell? Again, most likely. Would that person get the same level of support? I have had experience with this in the past, and I can say, resoundingly, no, because the first call I made, I got "Neal" with a very distinct Mumbai accent, and he couldn't do anything more than read me a script off his screen. And this was corporate support. I can't imagine the horrid state of consumer support.