I have enjoyed browsing through this thread very much. In fact, it has been instrumental in influencing me to get a K-3. I finally took the plunge! So far, I am loving it! Coming from a K-30, the AF is a big improvement and of course the build and ergonomics are quite a step up. I'm impressed with the high ISO capabilities as well.
Here are a couple shots I like so far. The second shot of my cat Shanequa is ISO 6400 and at this size, I find it more than adequate. The K-30 file would've been very smeared, but I like how the K-3 handles noise.
Thanks to all of you for posting such awesome images!