I deleted my account on LinkedIn about a year ago because I was wasn't getting any value out of it and was concerned about their security. After reading this post from David Veldt I am so very glad that I did.

I’ve concluded that LinkedIn is by far the creepiest social network. The primary reasons LinkedIn is the mustached, trench coat and wire frame glasses wearing mouth breather of the internet are the “People You May Know” and “People Also Viewed” features.