Are you ready for a sneak peek at tomorrow’s blockbusters today? Check out our new series “Behind the Screen” Sunday night at 11 p.m. on MTV for the broadcast premiere of the “Brüno” trailer, an exclusive clip of Brad Pitt in Quentin Tarantino’s “Inglourious Basterds,” the very first visit to the set of Russell Brand’s “Get Him To The Greek” and much more!

The killer MTV Movie Awards updates are coming fast these days. Earlier this week, we dropped a bomb about the “New Moon” cast presenting an exclusive clip from their upcoming “Twilight” sequel during the live broadcast. Now we can reveal that during the show, viewers will get an exclusive sneak peek at two summer blockbusters: “Harry Potter and the Half-Blood Prince” and “Transformers: Revenge of the Fallen.”

Daniel Radcliffe, Emma Watson and Rupert Grint will present (via telecast from England) a never-before-seen clip from “Half-Blood Prince,” the sixth movie adaptation of the J.K. Rowling boy-wizard book series. Megan Fox and director Michael Bay will be on-hand to show off a fresh clip from “Revenge of the Fallen,” the sequel to the 2007 box office smash about shape-shifting robots.

But that’s not all. Joining the list of Hollywood presenters will be “Transformers” star Shia LaBeouf. The actor is also competing in the Best Male Performance category for his role in the paranoid thriller “Eagle Eye.”

The roster of celebrity presenters already includes Will Ferrell, Lil Wayne, Denzel Washington, Cameron Diaz, Sandra Bullock, Leighton Meester and Channing Tatum, Sienna Miller, Abigail Breslin and Danny McBride, among others. Eminem is set to take the stage, where he’ll perform music from his new album, Relapse, and Kings of Leon will perform live on MTV for the first time ever, rocking out with their hit song “Use Somebody.”

“Saturday Night Live” funnyman Andy Samberg will host the 18th annual MTV Movie Awards live at 9 p.m. ET on May 31 from the Gibson Amphitheatre in Universal City, California. You can vote for the Golden Popcorn winners in each category by visiting MovieAwards.MTV.com by May 27. Voting in the Best Movie category will stay open through the live telecast.

Will the vampires grab more trophies than the slumdog? What was the year’s ultimate onscreen WTF moment? It’s up to you to decide the winners of the 2009 MTV Movie Awards. Vote now, and tune in on May 31 at 9 p.m. ET, when the big show airs live from the Gibson Amphitheatre in Universal City, California.