I'm not too fond of the applecare program COMPARED TO other store programs. Applecare is nice because it's right through the manufacturer, realtively easy, software support, and you know it'll be taken care of well.
The problem with applecare? No protection against physical damage. All retail stores (Ccity, bestbuy, comp) offer protection that includes accidental damage. I'm very familiar with circuit city's (but they don't have macs), and I've heard that best buy's is great. I recommend buying the store protection + applecare. That way you get software support right through apple themselves along with great tech support, and best buy can just give you a new laptop after two and a half years when you decide to chuck it out the window.