I never really looked too much at the LinkedIn API, I suspect for the idea to work well you'd probably need to scrape data from the frontend and preferably be connected to a few "super node"-esque people (recruiters, etc).

(You're welcome for what bits of chumby I touched. Of course I was just one developer in a team of wonderful developers and hardware designers. It was a great job and a lot of fun. I still haven't decided if we were a bit too late (introduction of iPhone and Android) or too early (explosion in hackable maker devices like Raspberry Pi). I guess a bit of both.