New York, May 17 – With the Presleys pushing a documentary, a CD and a book on the king, we figured it was only a matter of time before an official Elvis sighting. And lo and behold, the name was on the Riverkeeper Gala invitation. On closer inspection we realized that Elvis Costello was the one singing for clean water. Elvis brought his wife Diana Krall, and another singer, Tony Bennett, was in the house. Uma Thurman, Cedric the Entertainer, Dana Reeve, Christy Turlington, Lorne Michaels, Jon Bon Jovi, Edgar Bronfman, and a few Kennedys all assembled at the Chelsea Piers, and Arianna Huffington even took time off from her celebrity blog to attend. The gala was perfectly timed to honor Viacom’s Tom Freston, who, as a TV executive, has nothing much to do during Upfronts week. This being an environmental benefit, we couldn’t help noticing that most of the boldfacers drove up in gas-guzzling SUVs.