Wedding Etiquette from Emily Post

So I was wondering about wedding etiquette because of last week's episode of Mad Men. I decided that the most reliable source on this would be Emily Post. So as I was reading through the details on the site I came across two things that really made me laugh. First off was the etipedia, which is basically an etiquette encyclopedia. The second was in reference to the phrase second marriage. The site uses "encore weddings". I guess that would make more sense for a vow renewal because the bride and groom have changed. However, I'm definitely not the guide to any sort of etiquette it's up there with advanced Forex training in my brain. I just thought that it was a really lovely if somewhat confusing way of phrasing things.