It would be good to start with a specific audience (e.g. programmers) and use GitHub activity to factor in their professional experience as an example. I can see this being useful for recruiters to screen developer linkedin profiles.
The name predikt implies you plan on predicting something, but I am unclear what you are predicting. Potential salary range? How likely to leave current job? etc.
Right now, Linkedin and facebook integration are functional, certainly it would be more useful to add all possible networks. Github, Stackoverflow would be next. Some recruiters have approached and would like to use this for screening their applicants.
I think the recruiting industry can definitely use more help from technology.
Personally I like the idea. I have never heard of it before. Something like a Credit Score for profiles.