As a pro who has used Pentax bodies and glass my entire career (ES, K2, K2DMD, MX, LX, PZ-1, PZ-1P, MZ-S, 67, 67II, *istD, K10D, K20, K7, K5, K-30, 645D), I'm going to chime in and say this...it's all about making great photographs, and it always has been.
If you have a personal consistent vision, mastery of your craft and your system, you can make superior quality images with any number of cameras, but the glass is always the ultimate key. For me, the ruggedness and light weight nature of Pentax gear meant I could carry less weight and more optics into hard rough places, and come back with images that I could sell. I've made a good living for 30 years with Pentax gear, and still do. I've never had to apologize to any stock agent or photo editor for my image quality, and have been with Getty and Corbis for longer than the golden age of stock. They've always taken my selects.
And now, I still have lightweight, weather sealed, rugged bodies with a reasonable array of superb optics and more on the way. When the 645D surpassed my venerable 67's (with which I shot more than half of my 200 book and magazine covers), I went MF digital and just carried the 645D and 3 great lenses up to the summit of Mt. Whitney two weeks ago, and down the river in Grand Canyon this summer. Try that with an Hassy MF...
Can enhancements be achieved to Pentax bodies? Yes, of course, but I'll take the K5 over any FF monster out there at present. When and if Pentax does release an FF body it will still be lighter, with a smarter easier faster interface than the C&N folks could ever dream of. Until then I'm shooting travel features, ads, campaigns and more with the K5 (can't wait to try the K5IIs), the surprisingly superb K-30 (best low-cost APS-C body out there for me), and the 645D whenever I can use it.
I'll close by saying I've always taken a perverse pleasure in being unique among my peers, using Pentax to make a living and stand out from the crowd. Be an iconoclast if it suits you, and then, just go shoot the world. We already have access to higher quality imagemaking potential than I ever dreamed possible, and it's just getting better. My 2 1/2 cents, written from the road...
