How bittersweet for Prince William.
But will he sing?
Nope. He'll leave the piano at home, he will be bringing partner David Furnish along as his date.
The singer opened up about England's future queen too, saying she's very much like Princess Di "in personality."
"She is very discreet, she is a beautiful girl," he said. "They have been together a long time and I think she has handled the pressure so much."
Elton says that England needs a young person like Prince William to lead and that he will be "tremendous" when he fills the role.
As for the actual wedding, details will be posted on a Wills-and-Kate-sanctioned website, officialroyalwedding2011.org, launching today courtesy of St. James Palace. The site will run regular wedding , photos, videos and important links until the big day.