Disney does hate to leave $$$ on the table, but even I can't see them making the resort parking fees double what it costs at the main parking lots. I imagine it will be the same, maybe a few dollars more. If this is the case, I am parking at the Contemporary EVERY time I'm going to the MK. If I can skip the main parking lot in a valid way by paying a parking fee, I'm going to do it. I won't do it at the Epcot resorts, because they are not any more convenient than parking in the main Epcot parking lot, but it will be a benefit when it comes to the MK.
Disney is not doing this because they care about resort guests parking woes, nope, they don't care about you at all. What Disney cares about is $$$, and they see that people are beating the system by parking at the resorts for free. I'm betting that the parking fee at the resorts is going to be the same as the main parking lot, not as a deterrent, but as a way to catch that revenue that is currently slipping by.