Mac Book Battery Life
MacBook pro Retina is coming with a cycle count of 1000. Once this amount is consumed it is time for a replacement.
Need a long life time for your MacBook battery?
It is always recommend to use your MacBook plugged in when it is possible. This helps to maintain less number of cycles used.
When he needs a Calibration?
Newer MacBook’s comes pre calibrated and a calibration is not necessary. Find whether your MacBook needed a calibration though this link http://support.apple.com/kb/HT1490 .