I had been wondering about this topic for awhile now.
I had been invited to a jewelry party, via a postcard sent through the mail and also a conversation on the landline. Both invitations came from the hostess.
An hour before it's supposed to start, I'm getting changed for the party, looking forward to seeing everybody. I get a landline call, from one of the party participants.
She asks, "So, what are you up to?"
Me, "I'm getting ready for the party"
She says, "Oh! the party was cancelled."
Me, "Really? I didn't know that. Hostess didn't call me. When did that happen?"
She says, "Hostess sent out a message through FaceBook"
Me, <

> ,"I'm not on FaceBook. Hostess knows that."
She says, "Oh."
The conversation got really ackward after that. I'm still not happy about it when i think about it, so I try not to.