I have an early 2011 MBP i7 Intel and I charge and discharge the battery on a daily basis (i.e. charge it to 100%, disconnect mains, use it till it goes down to 5-10%, then charge it again). In doing so, it has rarely given me more than 3 hrs of battery time. I have ended up consuming 400 battery cycles in 8 months. On inquiring at various forums, I see that people recommend I should keep power connected to my MBP most times and let it drain only once in a while. I guess I will do that now and see how it improves the battery performance.