Sienna Miller  channelled old-Hollywood  posing with her costars and riding around in the air with Jimmy Kimmel in a "super cage" at the G.I. Joe  premiere in LA yesterday. Channing Tatum  held Jenna Dewan close while she showed some leg, but it was another set of newlyweds who were trying to get all the attention. Heidi Montag  and Spencer Pratt  took advantage of the audience to debut Heidi's new Playboy cover . They displayed bikini -clad Heidi covered in dirt, though she's not the only one known to strip down — Spencer's competing against Beckham in our Hottest Shirtless Guy  contest, so make sure to cast your votes .
To see more pictures of Heidi's Playboy cover plus Sienna with Jimmy Kimmel, Rachel Nichols and many others just .
Images include: Sienna Miller, Channing Tatum, Heidi Montag, Spencer Pratt, Jenna Dewan, Jimmy Kimmel, Sumner Redstone, Rachel Nichols, Adewale Akinnuoye-Agbaje, Aubrey O'Day, Ciara, Damon Wayans Jr, Marlon Wayans, Stephen Sommers