Before the upgrade I was able to leave my N800 on with a connection open while not using it for quite a long time and the battery wouldn't drain for days. Now if I do this the battery is all the way down just overnight. If I put it in offline mode the battery is fine and seems to last longer than before without charging. So for me the most important thing for a long-lasting battery charge is to remember to put my N800 in offline mode when I'm not using it. Too bad there's no setting to have it automatically go in offline mode after a set period of non-use.