Obviously this will all be wild speculation at this point. But what might Paizo's role be with 5e (or whatever the new iteration of D&D ends up being called)?
I think what there role
should be is "Continuing to kick the crap out of D&D".
Kidding & snarkiness aside, seriously folks, why should Paizo role over & jump on the 5e bandwagon? Several problems with this:
1. You're assuming that it'll even be an option. The GSL was an abomination compared to the OGL from a 3PP perspective. 4e, as a viable Hasbro product, was effectively called a failure today. The fanbase is fractured, Mr. Mearls says 4e over-empowered players at GM's expense, and WotC hasn't been able to produce decent adventures to dent Paizo's AP & Module lines. I think it's possible, perhaps even likely, that they'll court 3PPs this go round, but I seriously doubt they'll embrace an OGL that they discarded. Expect a less-restrictive GSL.
2. Paizo, by their own statements, had their best year in 2012. The Pathfinder business model is working,
whereas the 4e business model wasn't. When you're firing on all cylinders, you don't throw your business plan out the window
on the chance, your biggest competitor may make a good competing set of products.
3. Brand loyalty doesn't trump product quality, despite the "I'll play anything that has D&D as its name" crowd. Once upon a time, IBM mainframes were the pinnacle of computing and the expression "You can't get fired for buying IBM" was gospel. And then came the personal computer... Could WotC & D&D recapture the lightning in the bottle? Sure. Could Paizo supplant D&D as the "gateway drug" of RPGs? Yes. And right now, it's got momentum and a weakened competing game/brand in its favor.
4. Paizo has put a lie to the theory that adventures don't sell. Perhaps the older 20-30 page module doesn't sell like gangbusters, but APs are still the leading brand for Paizo. 5e doesn't just have to fulfill the stated design goals, it has to recapture lapsed fans, but also provide setting and adventure material that is at least enticing enough to make GMs want to run it.
Does Paizo have to continue to execute and adjust as necessary if 5e is a huge success? Absolutely. However, I hardly think that they need to fold on Pathfinder, throw control over their own destiny out the window, and hitch there fortunes to the 5e bandwagon.