One of the shortcomings of the very good K-5, and indeed all of Pentax's DSLRs, is the adequate if not outstanding autofocus system. The K-5 II (as well as the new "s" version) just might offer a real remedy in the new SAFOX X autofocus sensor. The K-5 II's autofocus is rated down to -3 EV, approaching moonlight levels, and should track moving subjects better than prior iterations. The LCD screen has also been upgraded to have no air gap, which should improve outdoor visibility. These changes are, however the only truly compelling upgrades. This isn't necessarily a bad thing - the 16.3 megapixel sensor, weathersealing, 100% viewfinder and Shake Reduction (SR) are all fantastic - but such incremental changes aren't likely to excite would-be upgraders. Pentax will also be releasing an "s" version of the camera for a $100 premium that lacks an anti-aliasing filter. Such a move should yield sharper photos but invites distracting moire in fine patterns.