You guys missed a very important advantage of Pentax K5; it is the world's most compact, solid and weather sealed APS-C DSLR compared to ALL in the market. Google on the 7D weathersealing and you will be surprised by how 'weather sealed' it is. Now google youtube for k5 water resistent test, any other doubts? The K5's long lasting battery, low light performance, great DR etc.... are really sweet too! For outdoor photographer weather sealing is of paramount importance and K5 is right up there with all the goodies. What these guys need is to have more screw drive (short throw) and a SDM II WR prime and zoom. Coupled with better AF algorithm and video and perhaps sensor upgrade we are good to go kill some giants!
For sports and fast action, I can safely say that after some playing around with AF-C I noticed that K5 can get the job done if;
1. set to FPS priority
2. set to f5.6 at least
3. pre-focus if possible
Applying the above techniques with a screw driven DAL35mm I was able to capture great action shots that have a second or less window of opportunity. Got to love the K5, it rox, REALLY!