My biggest question is why isn't there something better than Linked In? I get the network effect but Linked in is crap.
Because a non-crap product wouldn't be worth $26B. What you perceive as crappiness is the sauce that keeps you coming back.
There absolutely is something better than LinkedIn; it's email and phone contact. But everybody expects you to be on LinkedIn.
To solve the network effect you need something 10x better than what people are jumping ship from. Even if you had a cleaned up version of LinkedIn, it wouldn't be so dramatically better that enough people migrate to reach critical mass.