Sportscaster Len Berman returned to NBC for the first time since being let go in April after more than two decades at the station — and may regret his visit. In the “Today” show Green Room, Len, promoting a new book, saw real estate contributor Barbara Corcoran memorizing her notes. He said: “I thought you just ad-libbed that stuff.” Brassy Barbara replied: “Yeah, and I thought your hair was real.”