This entire debate on whether something is Pro or Semipro or entry level is actually moot. In the end, like others have mentioned it comes down to who is shooting and not necessarily the equipment.
If you get paid for your work, then I guess its acceptable to be classified as professional. Now after saying that, I have seen enthusiasts shoot some of the most amazing landscapes, never get paid, yet I feel their work screams..."professional."
I shoot with what I am most comfortable with, and am secure in knowing that the camera I choose is the tool that makes my job easier. Pentax just seems to do that best for me.
Other systems I have worked with have made achieving the decisive moment a little easier, but the prep time and obstacles by way of poor ergonomics and weight have prompted me to return to Pentax.
When my travel mag sends me on assignment to shoot a resort or a location, Im happy bringing the Kx and the lot of DA pancake limiteds. More than enough equipment to get the job done. It may be viewed as a toy, but I like to be discrete and perceived as a novice when Im working, so no distractions.
Shoot with whatever you feel suits your needs, that's photography