The other thing that can stop this is a bidding war, where credit card companies restructure their business model and lower their fees to the point where the inherent advantages of credit cards (such as chargebacks and lower inherent overhead due to lack of currency volatility and mining) stop the advancement of Bitcoin.

In either case, Bitcoin isn't going to take over the world, but whoever can figure out a good way to deal with the problem of how regular people could easily obtain Bitcoin in the first place has a chance to skim some profit in the interim.