I think what Buge is saying is that some user X used the "find my contacts from my email" feature. Linkedin hoovered all emails (and potential conversations) an

I think what Buge is saying is that some user X used the "find my contacts from my email" feature. Linkedin hoovered all emails (and potential conversations) and built a database of consisting of emails and conversations which looks like: nadams sent email to moron4hire etc.. But moron4hire does not have a linkedin account, so what linkedin will do when I sign in I'll see the ability to add that email as a connection (and thus send them an email asking them to sign up for a linkedin account?). I'm just guessing - for all I know linkedin has a crystal ball in the backroom.