Further to the last reports of the issue, it seems that the SR system of at least quite some K-7 units are having problem. See the latest report from yet another K-7 user just a few days ago:-
http://pentaxforums.com/forums/showthread.php?t=75494
Sample pictures with central crops are posted. It really looks horrible, as the poster writes. It just shows that the SR just *Added* Shakes, instead of reducing it, when the SR function was turned on.