What happens when the battery on the rMBP needs to be replaced?? I understand one can get Applecare to cover any battery issues (other then general wear and tear etc) for the first 3 years, but Im planning to buy a max spec 15" rMBP on the next refresh with Haswell, and will be keeping it for as long as possible. If it develops any battery issues within its Applecare coverage, do they replace the entire system since the battery is glued in?? How much does a battery replacement cost when outside of warranty, or is it too early to tell??