I'm closing my Google+, Facebook and LinkedIn accounts today. It may take a few days for them to disappear, but don't be surprised when they are gone.
If you want to follow what I'm up to there's always my Twitter account and I can be easily contacted using email.
My use of these services had atrophied over time and leaving them open was just leaving out of date information about me out there.
PS Deleting these accounts turned out to be pretty easy. G+ is instantaneous once you ask for the G+ profile to be deleted; Facebook was also instantaneous; LinkedIn insisted on sending me an email confirming that I wanted to delete my account and trying to persuade me not to. The LinkedIn mail involved community with a human and confirming in writing (by email) that I wanted my account deleted.