I'm a pilot and have worked plenty of density altitude tables...here in hot Texas. In aviation, density altitude effects engine performance and takeoff roll because you are working with air density.
Hiking altimeters are "temperature compensated" so yes, I believe density altitude is taken into consideration but is not anywhere near as important as in aviation. In hiking, you are looking for the physical altitude, not a 'relative' altitude caused by temperature. Am I saying this right? <img src="/forums/images/graemlins/crazy.gif" alt="" />