Over the past few weeks, we’ve heard more news about plans for Facebook’s payment platform, as well as reports of internal optimism about its prospects as a driver of revenue.

Tech pundits have frequently sought Facebook’s “killer app” for monetization. At first, it was Beacon. Then, it became realtime search. Now, it might be payment.

Facebook, however, might not have the same imperative. Unlike Google, which has a disproportionate amount of its profits driven by Google Adwords and Adsense, Facebook isn’t necessarily going to rely on one product to carry it. It’s easy to see brand advertisers, search advertisers, self-serve advertisers, and payment platform customers existing in an ecosystem together, and providing equal impacts on revenue.

Of course, understanding Facebook’s monetization strategy is like reading tea leaves for an outsider. However, though it may be difficult to make conclusions about what exactly Facebook plans to do, it’s easier to advise developers on the model. Facebook diversifies its revenue between a number of unique methods. Developers should do the same. It helps protect your apps and profit against saturation of certain techniques, user fatigue, and cyclical downturns.

As usual, Facebook may not lay out all the rules for developers. But it does provide great lessons.