I think Universal has a better shot of leapfrogging those parks than DCA. Carsland gave DCA a big boost, but the numbers seem to be leveling out now. They aren't losing momentum, but not really gaining either. Form the Q1 earnings call:
"Attendance at our domestic parks and occupancy at the hotels were comparable to the first quarter last year, in which we saw increased visitation due to the opening of Cars Land at Disney California Adventure and the grand opening of the Fantasyland expansion at Walt Disney World, the last phase of which we’ll complete in a few months with the launch of Seven Dwarfs Mine Train."
Maybe DL attendance is way down and DCA is way up but assuming that's not the case I don't see it leapfrogging any WDW park (unless it already did in 2013). Universal has a good shot, especially if either or both DHS and AK become big construction sites with slow moving projects and years of construction walls.