Playing devils advocate here, I can see what you're all saying about Pentax, I've used their SLR's for years, since I bought my first one actually which was 23 years ago, ( wow that's scary ), I don't know why I bought it then but because that's what I started with i continued along that. Until now, I want an DSLR and although I've looked at EVERYTHING it's come down to Nikon or Canon, and I still can't decide.
If they aren't selling record numbers they probably can't spend too much money advertising, it's all relative. Canon and Nikon obviously have the cash to throw at advertising, even Fuji regularly appear on the back pages of magazines and while I do see Pentax ads they're not out there, just in the middle of the mag.
Pentax are very well specified but I probably read too many reviews and maybe it's a bias by the reviews or something but they never quite come out as well for something or other which is a shame because they've got such good features ! the K5 interests me but to be honest I doubt it will be what I choose...