Folks,

Note sure if this is the best place to ask this one, but I doubt there'd be a better place. I see that github, stackoverflow, facebook, twitter, linkedin etc. have been providing developer API to slice and dice user information. Couple of questions on the general nature of these API: 

1) Are these open-source? 

2) Is there any general feedback on which specific programming language works best with these kind of 'social' APIs? In particular, any comments on whether C/C++ are suited for such work?

3) Is there any recommended C/C++ open source package for 'mashups' across social networks?