My truck sits alot, so I try to start it every few weeks or so and idle for 15 minutes. Or take it to the store and back. What is wierd is I actually have been driving my truck lately. I have put more miles on it from christmas til now than all of 2007 put together. I took it on a trip to the inlaws 4 hours away each way, then took it up to a resort couple hours away. Then I left the car seats in it, so my wife was driving it 3-4 days a week. Then I parked it a couple of weeks ago and that was the first time I tried to start it. I have let it sit for a lot longer than 2 weeks before.
I guess I will let it sit for a week or so then retest the batteries. I am really hoping it was a fluke like a light relay stuck on or something stupid. I think I would have noticed a light left on.