Alabanco: You don't have the same problem at all — in fact you have
no problem at all.
Appleinfl's MBP is not reporting any significant decrease in charge level after running on battery power alone for an extended time, apparently even when the battery holds too little remaining charge to wake from sleep. An SMC reset doesn't correct the problem, so a visit to a Genius Bar or a call to AppleCare is in order.
Your MBP is showing a trivial decrease from 100% to 99% after being left idle with the AC adapter connected. That's perfectly normal. The battery's charge level diminishes whenever it isn't actually being charged, no matter whether the machine is in use, asleep, shut down, or the battery is physically removed. By design, when the battery's charge level reaches 100%, charging stops, even if the AC adapter remains connected. Charging doesn't start again until the charge level falls below 95%. So during that interval, you will see the level fall to 99%, 98%, 97%, etc. This allows the battery to remain cool most of the time even if the AC adapter is connected nearly all the time. Heat is the enemy of batteries, and charging generates heat. The desire to limit heating of the battery probably also accounts for the much longer time it takes to charge current MBP batteries, compared to earlier models: charging at a slower rate generates less heat.
