The nominees for the 2009 MTV Movie Awards are in, and you should be casting your votes right now. So, with just weeks to go until the big show, we're now revealing our first set of Hollywood presenters.

Lil Wayne, Denzel Washington, Cameron Diaz, Leighton Meester, Ryan Reynolds, Will Ferrell, Vanessa Hudgens and Jonah Hill will be joining host Andy Samberg live on Sunday, May 31, at 9 p.m. ET for the 18th annual awards show. Eminem is also set to take the stage, where he'll perform music from his new album Relapse.

"High School Musical 3: Senior Year" star Hudgens is the one announced presenter who's also a nominee. She's up against the likes of Ashley Tisdale, Miley Cyrus, Kat Dennings, Freida Pinto and Amanda Seyfried in the Breakthrough Performance Female category.

"Twilight" lead the cinematic pack in nominations with seven, including nods for Best Movie, Best Female Performance (Kristen Stewart) and Breakthrough Performance Male (Robert Pattinson and Taylor Lautner). "Slumdog Millionaire" follows closely behind with six nominations, including Best Movie, Breakthrough Performance Male (Dev Patel) and Pinto's Breakthrough nod.

In addition to classic categories like Best Kiss, Best Fight and Best Villain, MTV is introducing two brand-new categories this year. Best Song From a Movie nominees include tracks from "Hannah Montana" (Miley Cyrus) and "The Wrestler" (Bruce Springsteen). Best WTF Moment selections honor such outrageous scenes as Ben Stiller tasting a decapitated head ("Tropic Thunder") and Amy Poehler peeing in a sink ("Baby Mama").

Viewers will be able to decide the Golden Popcorn winners in each category by visiting MovieAwards.MTV.com by May 27 to vote for their favorite films and actors. Voting in the Best Movie category will stay open through the live telecast, meaning any craziness that takes place onstage has the chance to affect the outcome.

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.

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