OK. First of all, i have owned a K100D, gx-1s(k110d), a A75 Canon, a LMZ Lumix, and so on. Plus ive played with the K10D before.
First off, my A75 had AWESOME battery life, it takes 4 AA's. It is an old digital camera, had a small LCD, didnt require to much power.
Then I had my lumix, which has a battery pack. It has a huge 2.5 lcd screen, lots of auto zooming, alot of stuff which take lots of battery life.
Then I owned a K110D, and the battery life sucked. I would have to charge the batteries after an hour or so of shooting. It takes 4 batteries. It has a decent 2 inch screen.
Now i own the GX-1S. Almost the same camera. No image stabilization. I get better, decent battery life. Still not as good as my A75, but thats because it has a bigger LCD, and more auto functions.
The K10D i took out for a day lasted without a hiccup. Lots of things draining the battery, but it still performed great.
'Nuff said.
Thats why if the K100D comes with a battery pack, i will buy it. Other wise, i may just get the K10D, but i was hoping theyd update the k100D because I like the size and weight of it.