you can get replacement/spare batteries in the original DMW-BM7 configuration, up to 800mAh. I have two spares rated at 750mAh which I got on ebay for $16 each, and they work perfectly. I can get between 175 and 225 shots per charge, depending on how i use the camera. if i'm planning on a long day's shooting, i take a spare battery and memory card with me, and leave the third battery charging at home.
Squirl033, don't know how you do it--I just spent a week at Long Beach (the Vancouver Island one), and each day I drained my 850mAh generic ebay batteryin 100 shots or so. The originalPana 680 mAh battery was only half drained with the same use. And I'm trying to saveenergy by setting camera to spot AF mode, spot metering, continuous AF off, Mode 2 OIS, auto review off,etc., and I use EVF almost exclusively (including review). I also speed up the startup by holding the zoom lever if I want zoom shots (saves the lens fromopening all the way to wide angle then having tozoom back out).
Anyways, I don't have confidence that I'll ever be able to get 200+ shots out of a charge, even the Pana.