Which will generate more money Pac/Marquez or Mayweather/Ortiz?

With regards to filling up the seats, I think Pac-JMM will do better than Mayw-Ortiz. You have to remember that Pac was able to fill up more than 50,000 seats (or was it 40,000, sorry but I'm unable to check without getting out of this page) in the Dallas Arena in his fight with a non-entity (Clottey).

I believe overall, the Mayw-Ortiz fight will generate more money on American soil (including PPV sales) whereas Pac-JMM will fare better worldwide.