At this point, you two are really just debating semantics, and what constitutes "market share" vs market position.
What still seems to be the case is that despite Universal's growing share of the market, they do not yet seem to be cutting into Disney's actual consumer base.
If anything, Disney is profiting as much from Universal's expansion as Universal is, since a lot of families make the decision to come or return to Orlando because of the new things Universal is offering, but still spend an equal, if not greater percentage of their time in Florida going (back) to Disney World.
Universal is trying like hell to change that and become their own 3-4 day all inclusive resort destination, and they're about a water park and a monkey from getting there.
When that happens, and assuming Universal can maintain the momentum they gained from the two Potter build-outs, things are going to get really interesting.