Originally posted by dws1117 So why would I want to go with one over the other?
I don't know, what are you missing?
The K10D has a rechargeable Lithium-Ion battery instead of using off-the-shelf AAs.
The K10D has an ISO range of 100 to 1600 instead of 200 to 3200.
The K10D is slightly larger and weighs 130g more.
The K10D has 10.2 MP instead of 6.1 MP.
The K10D has 2 dial ergonomics instead of one.
The K10D has "selectable program line" which lets you optimise Program mode for faster shutter speeds, smaller apertures or the optimum lens performance.
The K10D has pentaprism viewfinder instead of penta-mirror type.
The K10D has an IR remote sensor behind the body as well as in front.
The K10D has TAv mode that lets you set aperture and shutter and have the camera adjust ISO.
The K10D has Sv mode (sensitivity priority) that gives quick dial access to changing ISO.
The K10D has hyperprogram mode with its Green button.
The K10D exposure compensation is +/- 1/3 instead of +/- 1/2.
The K10D has dust and weather seals.
The K10D has a dedicated RAW button.
The K10D displays separate RGB histograms.
The K10D has a larger buffer so it can shoot 10 RAW images at 3.1 fps, as opposed to 4 at 2.6 fps.
The K10D supports SDM lenses (as does the K100D Super).
The K10D has a dedicated button for auto-exposure bracketing.
The K10D has an optional battery grip.
The K10D can save to Adobe standard DNG format RAW files, as well as PEF.
The K10D has in-camera RAW development.
The K10D does not have picture and scene modes.
The K10D is operationally faster, about double the speed of the K100D.
I find the first three to be good reasons to stick with the K100D, but all the rest of the advantages are with the K10D.