Facebook maintains a large community developer base. Some of these developers are responsible for the well-off Farmville and the like. If the user base is there so will there be developers with dollar signs in their eyes.

Anyone who likes can view the API for free and start writing code. This availability– plus the large user base– is proving to be a fertile ground for mom ‘n pop-style, web-based applications. Perhaps this is worth a look?

Update 2010.04.10
After spending days researching this I have come to the conclusion that there is virtually no documentation of substance. Even the Facebook-supplied examples do not function as promised. Although there are some great, complex applications out there I do not consider this worth my time right now. My hat (and my pitty) go off to the people who got a job working with these APIs. May your families find another way to eat.