Shake reduction and not-quite-live preview.
Now, you may ask, why not just take a picture and preview that? Well, Digital Preview does save you space on your memory card-but then, you can always erase a picture from a memory card. Kind of gimmicky, we say. And you can always program the depth-of-field control (via custom function) to stop down the lens to the shooting aperture for conventional depth-of-field preview.
The eagle-eyed may spot another subtle difference on the topside mode dial. Instead of just a basic all-auto mode, you'll find a scene-mode position, where you can choose, via the menus, from an additional eight scene or subject modes, besides the five already on the dial. The new ones are Night Scene, Surf and Snow, Text, Sunset, Kids (which promotes "healthy and bright skin tone"), Pets, Candlelight, and Museum.
While the K100D uses a 6MP CCD like the *ist DSLRs, Pentax says that the processing engine and firmware are new, and that the camera will ship with improved software.
Still, we were more than a little surprised that Pentax didn't opt to move up to 8MP or 10MP capture with the new camera; 6MP DSLRs are getting very old at this point. The company was clearly determined to hew hard to a low price point with the K100D, and it certainly succeeded. For the even more frugal, a K110D-the same camera but without Shake Reduction-will be available for $599 with the kit lens.