[pasbesoin]

Facebook is in business for Facebook.

They're willing (and smart) to leverage independent efforts where they assist this. But... only so long as they do.

Look at it from this perspective: If a functionality becomes important, would they not be "derelict" in their duty not to attempt to bring it under their control? In-house, acquisition, whatever.

If you choose to help them out, they're not going to say no. But you should keep the balance of power in such a relationship in mind.