It's Facebook for professionals. That's all it is.
I don't think it's quite that simple. There's very little 'social' aspect to LinkedIn, while Facebook is almost
entirely social, in nature. LinkedIn also seems - to me, anyway - to be more purpose-driven (get a job, recruit an employee, etc .). After you've fully utilized the 'connect' aspect of Facebook, on the other hand, it seems kind of pointless to me and more of a time-waster. I'm sure I'm in the minority on that, but that's my perception. That and I really don't give two sh&%s what someone's "status" might be, nor do I actually believe they care about my own

.
I think about the only thing they have in common is that they are both made for connecting with others. But the reasons for that connection are what make them so different.
I've been on LinkedIn, but don't really 'use' it, mainly because I'm not looking for a job right now. I
have been able to connect with some helpful individuals in my field who work for various state, federal, and foreign government agencies; as well as non-profits and similar conservation groups. That's been a great benefit to me. I also plan to retire and move to a s econd career, eventually, so maybe I'll be more of a LI 'user' at that time.