The 7D is calling ... because I really really want an MPE-65 and there is NO other lens like it in the whole wide world (it natively does from 1:1 up to 5:1 macro for those who don't know the lens) !
However, that is the only reason I could find so far for supplementing my growing Pentax system, and I really don't see any reason to change now that Pentax have come out with the K5 and, from all indications, fixed the weaknesses of the K7 (notably high ISO and added a speedier AF, though the K7 is no slouch).
As for forums, I can only echo Kjell, well this is home, a great mix of people, expert assessment and assistance, and a very friendly atmosphere. I'd love to meet some of you in person someday.
Now and again a venture forth into other forums but this is my only regular (though until mid-November I'm afraid my daily visits are going to be curtailed, as they have been for the past month, by work etc.).
: 15 Ltd, 77 Ltd, 43/1.9 Ltd, Cosina 55/1.2, DA*300/4, Contax Zeiss Distagon 28/2.8, Raynox 150/250, AFA x1.7, Metz 50 af1.
: D800, D600, Sigma 500/4.5, Sigma 120-300/2.8, Zeiss Distagon ZF2 - 21/2.8, Zeiss Distagon ZF2 - 35/2.0, Nikkor 85/1.8G, Sigma 50/1.4. Nikon x1.4 TC, Sigma x2.0 TC