I have seen people post a photo of a wedding invitation on Facebook (wedding guests posting photos of invites when they receive it in the mail) and tagging the bride and/or groom in the photo. It seems rude and obnoxious, as if you are rubbing it in the faces of all who are not invited. It also seems wrong because the bride and groom might want to keep their day more intimate, and posting the details of the day online not only gets extra noses in your business, but it could result in some unintentional guests.
I eloped and invited no-one, but if I had sent out invitations, and one of my friends posted it publicly (regardless of their intentions-maybe they are just excited), I would ask them to take it down. Has anyone shouted out to the online world, "This is a major etiquette blunder!!!!"? Am I the only one that is mortified for the bride and groom when it happens?