[d2xdy2]

Perhaps purely anecdotal, but in the years I've been working, I can't say I or anyone I've talked to has perceived an opportunity cost in not having / ignoring LinkedIn (especially the folks who had one and then got rid of it)

I've really only ever received an inordinate amount of entry level recruiters "connect" with me using the same canned email they send everyone. I thought the references feature was nice, but the past few places I've been at have officiously discouraged using the feature because of PR issues (I might personally give someone a recommendation which could then not actually represent the company's perspective of the person)

In my opinion, LinkedIn is just a very creepy and annoying service.