If pentax had in lens IS
Also, as I just read this in-lens system suppresses moire so no aa filter is necessary?
Pentax IS is at the sensor, not in the lens as Canon and Nikon. It is the sensor vibration mechanism that sets up a carefully controlled amount of blur to avoid moire, whereas other cameras use the micro-lens AA filter on the sensor to create a small amount of blur to the same effect.
IS at the lens is usually reckoned to be more effective, but the pentax IS (like Olympus) can work on all lenses - saving the need to buy IS equipped lenses.
If I wasnt invested in Canon gear, I'd be tempted to try my father's lovely manual lenses on a Pentax, to see how effective the IS at the sensor might be. On the other hand, if Pentax launch a full frame DSLR, I might sell up and switch.
Pentax just may have its break here...