After almost a year of allowing third party developers a passage to get their applications directly onto Facebook; it is now turning a part of its application platform to open source as announced by the company (download available).
According to the company, more than 24,000 applications have so far been built on the platform with the number of developers building them reaching beyond 400,000. Stats show that 140 new applications are added everyday and almost all the Facebook population has added at least one.
The step has been taken to provide developers a view of the social networks platform and to give back to the developer community. The idea is to let newer ideas to make way into the platform to make it more effective and improve it. This would mean a lot, since developers can add functionality, their own tags and API methods. As people put it is an opportunity for the developers to show their creativity just as they did with the Facebook platform.
The release is licensed under the Common Public Attribution License (CPAL); which would also enable you to connect your brand with theirs, as you modify them. This excludes FBML parser (that has Mozilla source code).