Ye Waverly Blog, one tipster claims, is written by Carter's onetime executive assistant Jon Kelly (pictured below), recently replaced in that gig by the Observer's David Foxley. Here's Kelly's profile in the June 2007 Vanity Fair (from this):

Though it's sad to lose the mental image of Spy co-founder Carter anonyblogging, Kelly does a mean impression, and his ghost writing frees up Carter for host duty at the Waverly. In the April 1 video below (via Grub Street), Carter welcomes Bianca Jagger, first wife of former Rolling Stones frontman Mick Jagger - and rescues her from heading up the wrong flight of stairs, to the townhouse above the restaurant.