Hi, I've got brand new MBP '13 mid 2012 just last week, fully charged it before turning on first time.... Everything works fine, but I noticed that the battery drains slightly even though I never used\left the MBP without power adapter yet... In a course of the week it went from 100% to 97%. I never had the battery discharge like that with either of my prev. MacBooks and , actually , non Apple laptops either... Anyone can explain that? P.S. I do not plug into MBP anything else but wireless mouse. P.S. I do not use processes that would use too much laptop power either... I.e. - I do not believe that I exceed power adaptor's supplied power.