While the Santa Clara stadium is a little bit outside the scope of this blog, most of the people that are going to fill these seats are San Joseans. The Niners have already sold a staggering $670M in seat licenses. This is more than any other team in history 2 years before opening. Selling every single seat before the 2014 opener seems like a sure thing.
The good news for San Jose--besides residents having easy access to games with no taxes or financial risk--is that there are not many pre/post game options in the immediate vicinity of the stadium. That means that a lot of people are going to hop on light rail, and go to the nearest hub for the pregame or afterparty, and most of those places are going to be in San Jose. You can also expect San Jose hotels located near light rail to do very well on game days.
As a side note, this also shows a very strong market for professional sports in the South Bay, and should be additional evidence for Lew Wolff and the MLB to get their act together and allow the A's to move to Downtown San Jose.
Source: The Merc