as long as ortiz puts in a good performance against floyd and the undercard is stacked there is no reason why it won't be PPV.
If Ortiz and Berto both win their fights than I think a rematch could definitely be on ppv. I'd prefer it not to and it wouldn't be my first choice for a ppv but I can clearly see it happening. If Ortiz upsets Mayweather than he'll move into the position of being a fairly big star. Their first fight was very good and the rematch would be a unification as well. Putting a rematch on regualar HBO could go a long ways to making the winner a star, especially if its Ortiz, but if higher ups see a nice profit by putting it on ppv then I think it could land there. Neither guy is going to make insane money so its not like it would need a million buys to make a profit. Actually, if Ortiz were to upset Mayweather I think he looks for bigger things than Berto. A Mayweather rematch, Pacquaio, or even Khan. If Oritz loses than I think its more likely he faces Berto in a rematch but it would obviously be regular HBO at that point.