We knew Raising the Bar‘s Mark-Paul Gosselaar was a good sport when he came into EW for a meet-and-greet last year, faced a room full of entertainment junkies reenacting scenes from Saved by the Bell (okay, that was just Tim Stack), and fed Annie Barrett cupcakes. But doing an entire interview on last night’s Late Night with Jimmy Fallon as a grown-up Zack Morris gives new meaning to the term. (Maybe he was game because he got to perform Zack Attack’s “Friends Forever” with the Roots? UPDATE: That was one of Gosselaar’s conditions. He talks all about the appearance here.) The big news — other than that Zack never upgraded his cell phone and Fallon does an excellent “time out” — is that Gosselaar committed to Fallon’s Saved by the Bell reunion and announced that Elizabeth Berkley is also in. That just leaves Tiffani Thiessen and Dustin Diamond, who’s supposed to be penning a tell-all about the show. (Mario Lopez, Lark Voorhies, and Dennis Haskins had already RSVP’d yes.) Are we excited about this idea now?