If you need low light the k-x hands down,
Action k-x and 450d, both are good for that.
HDR shooting the panasonic is a excellent tool for that when shooting with a tripod and lower iso as they can do 5 frame bracket. Also it is a good travel size camera.
Super Frequent Flyer, no joke. Ex Patriot and loving it.
Canon Eos 60D, T1i/500D, Eos1, Eos 630, Olympus EPL-1, and a part time Pentax K-X shooter.