Mine had the original pentax battery in when it locked up. I believe it still had a decent charge in it when it happened too, but I'm not so good at charging religiously. My k10 went flat during the cerermony on my own wedding day .....

I got to say that I'm really quite happy with the frame rate available, but what I'd really like is the ability to shoot time-lapse movies in movie mode so as to not wear out the shutter mechinism. I figure 1080P is a high enough resolution for what I need movie wise and saves having to crop and resize every image in a timelapse.
I swear somehing like this can be added with just a firmware update. ....