yeah apparently the macbook battery doesnt exactly charge even thou its plugged into the ac 24/7.
urm read it somewhere, so i dont knw to what degree this statement is true. but the adapter is not connected directly to the battery. thats why when you flip the mac the other way around, the adapter is at one end and the battery is at the other. there is a chip that only lets the battery charge when its not full. when it is, the power go directly to where its needed and not to the battery first like any other device is designed to.

yeah but keep in mind that i read this of sumwhere and im not to sure of how true this is.hahha think the sifus over here will prove the statement after i post this up.

yeah no power is used. similar to charging your phone:
if the phone battery is empty and you charge it, you can feel that the charger becomes hot. but when its full and you leave it plugged and on, you will notice that after awhile the charger is not hot nemore.
same concept.