There has been plenty of speculation about this topic, but no hard numbers up to this point. On the heels of an up and down 2008, and a significant price increase to help fund the stadium expansion (and having to pay for a terrible home slate this year), 90% of season ticket holders renewed in what is a very difficult economy. For context, Wisconsin (at a larger stadium) also had a 90% renewal rate. Like Wisconsin, RU was at 99% last year.
Though Rutgers had a waiting list of approximately 12,000 (seats) for season tickets, Pernetti said that just 34 percent of those waiting have opted to buy season tickets.
That's relatively good, and from what I've seen, the numbers work for expansion at that renewal rate (they didn't use full capacity for the projections). The bad news is that with 11,500 additional seats in Rutgers Stadium (by the way, it sure would be nice to sell naming rights at some point) replacing the old South Endzone temporary bleachers, the athletic department has burned through the waiting list and hasn't sold every new seat. That doesn't mean there won't be sellouts, but it would be nice to have peace of mind as soon as possible. Games like Cincinnati will have strong demand for tickets, but you wonder about the walk up crowds for the likes of Texas Southern (at least it's homecoming).
Please correct my figures if they're wrong, but pre-expansion Rutgers had 28,000 season ticket holders (in a stadium seating 41,500, plus the temporary bleachers for students, plus the new Mezzanine last year), holding the rest for students and other purposes. So based on a 90% renewal rate, and 34% coming off the wait list, the total number of season tickets sold has actually increased somewhat from last year (to approximately 29,280). Back in March, Tom Luicci said that the new goal was 40,000 season tickets, meaning that the 11,500 "new" seats go towards season tickets. There are still three months to sell more season tickets, and Rutgers did have a strong walk-up tradition before 2007. Single game tickets still aren't on sale.
If my guesses are correct, then a "limited supply" of tickets available is a bit of an understatement. There would be over 10,000 left, albeit most located in the upper deck and the end zones. I assumed there would be less (increasing amount of student tickets, visitor allotments, etc...), but am basing this off the 40,000 figure.
There's not really more to say on this topic until the season approaches, and we know how sales are going at that point. It might be a good idea to start an advertising campaign. Even if one isn't necessary to sell all of the tickets, it could help get a buzz going and whet everyone's appetite for the new season.
edit: per Aditi, Pernetti's estimate is around 30,000, which includes student packages. At least he's being frank about this.
edit2: per Luicci, the official capacity is 52, 454, and "7,000-9,000" season tickets remain unsold.