I was there. There were about 5-7,000 empty seats. It is true that people are late arriving and disappear at half time but at its fullest there were noticeable empty seats. If they sold 70,000 odd tix out of a 75,000 capacity with a couple of thousand no shows it sounds about right. It was a good crowd but certainly not totally full.
The orange seats stand out, but they are still empty. Almost every NFL stadium I go to has a good number of empty seats even when they are sold out - Seattle last week was an exception where there were no more than 300 empty seats. These days, with teams selling season tickets to people who have plenty of money, and a lot of club seats at each stadium sold to sponsors, there are a lot of no shows in almost every NFL stadium.
BTW the reason the Orange bowl always looked full is because of the bench style seating - someone sitting down hides the view of the seat behind them so it looks full even when it isn't - this is why the college stadiums with bleachers always look full even after half time when people are still out the back.
The best thing about the new stadium is the lower capacity. At 65,000 we will probably be pretty full assuming we are doing well.