Remember with older type batteries the advice was to discharge them completely from time to time to improve their life and performance?
Apparently that is actually the wrong thing to do to lithium batteries, which the Droid uses. Lithium batteries do not have "charge memory" like the older Nickle Cadmium and Nickle Metal Hydride batteries did.
Read the posts by TheAnswerIs on both pages of this thread on the Motorola forums,
The number one cause of short battery life.
I started searching for other sources and his answers about avoiding deep discharge seem correct.
Here's an interesting article:
How to prolong lithium-based batteries
It says the same as the thread above about avoiding deep discharges. Except that you should store spare batteries at 40% charge and in a cool place, even the refrigerator. And they say to try to avoid keeping fully charged batteries in a hot environment, like a hot car.
I just wanted to prevent others from continuing the old deep discharge advice which is bad for the Droid's lithium battery.