I agree with you Bokehboy, but I think I can explain why you'll keep seeing these treads for the next 20 years too (except of course that Pentax might bring out the next world leading camera in a month or two, and also, who really believes there will be anything like SLRs in 20 years)... To the outsider, new to DSLRs, all these SLR cameras look alike (at least they did to me a few years ago when I was researching what to replace my AE-1 with), and if you believe these type of threads, there are no advantages to any particular brand (note how many people in this thread have said that Pentax AF is up to any action shooting - as good as Nikon or Canon). With that in mind many people choose the feature set that most appeals to them in their price range, and based on that Pentax is an appealing brand.
Rightfully so, as they are great cameras in their class, however, some people (like me) aren't good enough photographers to use Pentax for action shooting (limited by the AF, ISO, FPS to name a few acronyms), so when we find out that other brands actually offer a distinct advantage in those areas we need a crutch in
some of us feel betrayed by the brand we chose (I didn't feel betrayed actually, but I did feel it was time to move on). We can't be happy with our Pentax camera's faults knowing that our friends, the Joneses, are getting sharp shots with their C. or N. gear while we cannot due to our (our camera's?) failings... I sold all my Pentax stuff (well, I still have a P3n and a Spotmatic) and went to Canon and couldn't be happier
.
Note, it's not the camera
brand that is better... I won't say that switching from a K-7 to a Rebel would be an upgrade (I've never shot a rebel so I don't know (I bet AF would be better on the rebel
))... the difference is that the other brands offer an upgrade path - there are camera's higher in the lineup which offer higher performance than the top Pentax model.