I am so glad that the crowds have shown up after the lackluster Aug. opening. But I was pretty sure this would happen. Not because of RotR amazingness. But simply because for 3 years, late fall was the opening timeframe given. WDW's trip planning cycle starts about a year out. So people had already planned early Dec. trips by the time the Aug. opening was announced. Considering that the early opening announcement said RotR wouldn't open with the land, few chose to change their plans. Now that we are in the timeframe of the originally announced date, the crowds are here. Surprising, huh. And remember, there are still those that want to see it, but didn't want to deal with opening period crowds and planned a Jan. or later trip.
These are the crowds Disney was looking for.
Edit: They have changed the procedure for getting in a second boarding group. You cannot join a boarding group for a second ride until you exit the ride. They have Cms at the exit scanning Magic Bands at which point you can join a new group. This should help get more folks through the ride today.