I've had 2 Droid X batteries swell up. The first time I noticed was after I hadn't used it in a couple months. I plugged it in to charge and noticed a big "wet spot" under the screen, which I googled and found to be due to swelling battery. Sure enough, my battery was swollen up and I could barely get the battery cover off. I ordered a new battery, and it was fine for a couple months, until the phone completely discharged last weekend and I didn't use it for a couple days after that (it's an extra line). I just picked it up and noticed the same "wet spot" under the screen. The battery has indeed swollen up. Only a few days of being completely discharged and sitting in the phone and another battery is ruined. Pretty flawed battery design if you ask me. I can't even store it completely drained and unplugged for a few days?