Second, he stole not just "an idea", he stole the code, he participated in their in-house discussions and effectively was spying over his future competitors, and most importantly he stole a lot of time - ConnectU founders were lured into believing that their product was moving along for a while.
Nobody pays $65M in a settlement for "stealing an idea". The fact that Facebook settled for such amount only means that ConnectU lawyers were able to prove some of these nasty things above.
Personally I'm very disgusted by this accident, I regret that jail time wasn't even a question. Something very similar happened to one of the startups I was involved in, but in that case it was an opposite spin: an "idea guy" who contributed nothing but the idea, used cofounding developers to build a prototype and then diluted them to almost zero even prior to A-round.
This undermines the entrepreneurial spirit. And the fact that you can get away with it (like Zuk did) in such visible manner is even worse, it's like O.J case for software.