Thank you pageoneresults for all the information on this issue!
You're quite welcome. I'm on a mission this week to make this as public as possible before it's too late. Some are probably not taking this as seriously as they should. :(
My brain is hurting too and I am overwhelmed. Maybe we need to make this a topic at the conference in Boston.
I'll second that and also suggest that it be made a topic of discussion at all conferences.
I emailed my host about this problem since it said "Fail" on the Open DNS Servers check. They emailed me back and said: The Open DNS Servers fail you see is because CPanel allows recursive DNS queries by Default. If we restrict DNS Queries, your DNS server can't be used to query any domains, other than the ones you host in your server.
I'd ask them to correct the issue immediately or I'm going to have to take my hosting business elsewhere. Maybe not in those exact terms because I don't want them shutting down services while I'm making the switch to a new provider that passes the Open DNS Server test.