I have to say. I sometimes don't know. However, it will help your resale value a few dollars, if you sell it after year 1, but during the 3 year warranty still, if you had Applecare on it.
It's pretty affordable on iMacs, which is good because they would probably be less likely to break than a notebook, which by some people, get banged around a bit.
I've had it on my Powerbook and two iMacs, and so far I've only need it to replace an adapter, or a mouse, but hey, it was even nice then. knock on wood. I'd rather not have to use it even if I have it!
Now on a Mac Mini I have to wonder if it would be better, to just buy a new one, if it broke, with the lower price tag, same with Apple TV for example. Now with iPod I get it, to have battery done at end of year 2, if needed.
Finally, there is a potentially other solution! If you don't have too bad money troubles and are good and saving money and not touching it, everytime you buy something where an extended warranty is offered, you could put the same amount of money into a savings account. This would add up over time and could cover the cost of most replacements eventually.
Well, I'd probably just still get Applecare, for now. ha-ha. However, I do not buy applecare until 11 months into standard warranty. There is *NO* point to give APple your money 11 months early!