[LowVoltage]

I know there's little point in speculating, but can anyone speak with any certainty about the upward compatibility of the existing accessories for the K-7 and K-5 with a future replacement?

The choice to go from the K-7 to the K-5 was easy due to the fact that, in addition to all of the technical improvements within the DSLR itself over its predecessor, the K-5 could use the battery grip and quick release plates I had from the K-7. That saved me a ton of money. I'm curious to see if Pentax will bother to dramatically redesign the K-5's successor, if at all, requiring a new grip and other accessories.

[Adam]

You'll probably need a new grip and maybe a new battery/charger, but everything else should remain compatible.

[LowVoltage]

You'll probably need a new grip

Darn. Because the new grip will mean new contours that will likely not match the shape of my existing Kirk anti-twist quick release plate or the Mestos L-bracket. The L-bracket was a God-send, as it allowed me to use the grip with the body in the vertical position and still have the weight centered on the tripod rather than hanging off to the side of the ball head. I had to wait a good six months for Mestos to manufacture more and then wait for it to ship from Korea, but it was worth it. And of course, the Kirk and Really Right Stuff guys can't be bothered to produce and L-bracket that works with the grip for us second-class Pentax citizens... (sorry, mini rant done)