Here's a little known rule of etiquette: allowing someone's to jump like a madman on your couch does NOT equate to a wedding invite.

Oprah Winfrey has discovered this the hard way.

The talk show goddess let Tom Cruise famously act like a fool on her show, but that doesn't mean she'll be attending his wedding in Italy this weekend.

"It's not that I'm not going," Winfrey said. "It's that they had a limited number of people that they could invite. I was not one the invitees. That's fine. I don't get invited to everyone's wedding. I don't invite them to everything I do. But I wish them the best."

Taking the snub like a trooper, Oprah said she was trying to think of what to purchase for Cruise and Katie Holmes.

"I don't know! I was thinking … I'm easier (to shop for) â€" you can get me a bubble bath I'm okay â€" but I don't know what to give them."

Well, we already know the bride-to-be has absurdly expensive lingerie. Maybe Winfrey could get the couple a house in the Bahamas.

We hear Anna Nicole Smith won't be using hers must longer.