2.5 Battery only reports ~96% on full charge
This is a function implemented on ALL 2.2.1+ ROMS (including MIUI, which is based off CM7 2.3.3) so that the battery of the devices do not overcharge. Samsung ROMS falsely report 100% charge, but in actual fact, it also charges to ~96% and that if you watch closely, after a few minutes, the battery will rapidly drop back down to ~96% and stablise.
http://batteryuniversity.com/learn/a...ased_batteries