Who's behind the Little Brother billboard?

Over in the Wicked Good Conference, Crayonmoonbeam wonders who put up that billboard in Kenmore Square. The Web site doesn't say (and the domain registrant is "private"). Ron Newman speculates:

Since the last organization (of many) listed on their website is the American Hunters & Shooters Association, and their president is John Rosenthal, who owns property in Kenmore Square .... I'm going to guess it's him. But I could be very wrong.

Little Brother watching Tom Menino.

Update: Campaign to save the billboard.