Isn't it bad for LI-Ion batteries to let them go down to 0%?
On the battery life discussion, mines improved loads since I got it:
-gone through a few cycles seemed to make it much better
-got rid of logging and stuff with preware patches.
-turn off 3g data when I'm not using it using data toggle through preware
-Use wifi when I can, have it go to sleep when not in use or off altogether when out.