Apparently gingerbread stops charging when the battery gets to 100% . I guess this puts less wear on the battery. But it is kind of frustrating to wake up with a battery of only 70 or 80% given the that the battery life on these devices isn't great. On mine I never get 24 hours anymore, but that's probably due to daemons.
Maybe a charging schedule could be implemented in some way, like "next Alarm minus average charging time" ?