I recently read of a family of long time season ticket holders in New York scrambling to come up with the $80,000 they'll need to pay their PSL fees so they can purchase their season tickets.
Personal Seat Licenses (PSL's) aren't actually new, they have been around since the late 80's, and 14 NFL teams actually have some version of the PSL in place. The Cowboys, Giants and Jets PSL's go in effect with the opening of the new stadiums.
The way the PSL works is that you have to purchase the license for your seat prior to purchasing the season ticket for such seat. Once you pay the PSL that seat is your's as long as you purchase your season tickets every year. The owner of the PSL is free to sell it to anyone at any cost. However, if you fail to purchase your season tickets, the PSL is turned back to the team for resale.
I can't state why the Personal Seat License was created in the late 80's, but today it is used to offset the owners cost of the stadium. I believe Philadelphia actually calls them Stadium Builders Licenses (SBL's). The owner doesn't get the City to tax the locals for the cost of the stadium, so he put's the burden on the season ticket owners.
The Giants stand to make some 340 million from the sell of their PSL's that are sold for $5,000 to $20,000 per seat, depending on your seat location. The Jet's will sell PSL's for the same building. Between the two sets of New York fans, they should almost pay the full cost. Of course since everything is bigger in Texas, the Cowboys' PSL's will range from $15,000 to $150,000 (and somebody is actually going to pay that). Of course if you're building a billion dollar stadium, someone has to pay.