I believe our server was doing some scheduled maintenance during that time. Since it is our beta site it doesn't have quite the same uptime as our main site does, and we do more updates/maintenance.
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 .