I did a factory reset yesterday to see if that would jump start the battery indicator into behaving itself. I thought it was working even though I was a little suspicious that the battery was draining too slow. I checked the battery stats - 50% discharging with 12h 34m remaining (!) - and 10 minutes later, the Arc shut down due to low battery.
I am going to give it another day and see if anything changes. If not, I'm going to head over to Future Shop to exchange it.
Does anyone know if you can "overcharge" a device nowadays?