I'd vote to limit interest, and rollovers on payday (or title, or whatever short term) loans. Yes, it'd hurt the profits of some of these companies, but it'd also save a lot of poor people from ruining their already fragile financial situations. If the availability of these loans becomes scarce, there's also another option... a non profit entity, such as local governments, or charities, entering into the market.
It's a sticky situation, with no real easy answer. The best thing, for the moment, is educational movements, which hopefully videos like Oliver's delivers.