LinkedIn is not a social network. It's a site which holds my CV and then recruiters message me with Job Specs. I either like the spec or don't, and sometimes I get interviews from it.

I accept any friend request from recruiters/colleagues and beyond that never ever use the site.

My justification is I like getting job specs, and the cost is essentially nothing. Sure I hate that it's got a side panel asking me to connect with an old Wheel of Time fansite e-friend from Norway who was in my email contacts and I've not spoken to in some 15 years but it's hardly the end of the world.

"Social" in the sense of leveraging (exceptionally aggressively) the social graph and personal connections.

Less so in terms of content / context.