Aww okay! So AppleCare is a great investment if I plan on selling it within the next 3 years. So since I have a year to decide before the standard warranty expires I'll hold off buying it until we know if there's actually going to be a 2016 mini.
But then of course if the new model, by some strange twist of fate, is superior to the 2012 model in all ways then the 2012 model wouldn't be worth much anyways. Hmm.
AppleCare can be an investment, it can also be throwing money away . Yes it's a safety, yes you can sell a machine for a little more with AppleCare, though you will not get the money you paid for apple care back in the resale.
If you are buying a device that is going to be pushed hard, something like intensive CPU / GPU tasks, get AppleCare ! If you are going to buy a machine that is going to have a really easy life, don't bother, with all the apple products I've owned, not a single one that I've really looked after and had and easy life failed. Of the machines I used for intensive tasks, everyone has been replaced under AppleCare.
I cannot see apple giving back upgrade ability in the future for any product. 2016 will be like the 2014, and it will not have a quad core. Expect 2016 to be a small increment of 2014, though I doubt apple will update the mini till 2017..