Unfortunately, as is the case with all social networks, the functionality is secondary. Ubiquity is the game and sometimes that momentum is established just by being first.
I'm unsure if I'm doing it right but I've never used LinkedIn to secure an interview or job for that matter. I haven't met anyone who had done the same either and my Facebook LinkedIn friends list is basically 1:1.
I wonder what it would take for a MySpace Facebook migration for LinkedIn.