I think it's the third GJ because I seem to remember watching the first one when I was really down in the dumps and not expecting to watch the second, which I did.
When you block a person, they can no longer invite you to a private message or post to your profile wall. Replies and comments they make will be collapsed/hidden by default. Finally, you'll never receive email notifications about content they create or likes they designate for your content.
Note: if you proceed, you will no longer be following .