The oem pads (Mopar premium line) and rotors on my 2005 have nearly 100k miles on them and are still good to go with no excessive dust. And that's with driving in mountain terrain, though the manual transmission helps keep brake wear down ALOT.
I can't say what might be going on with your brakes, particularly if they are aftermarket pads or rotors, but excesive dust would indicate that something is wearing down-- a quick wheel removal and inspection would at least let you see what is going on and also look for any problems.