Country music's biggest stars hit the red carpet in Las Vegas last night for the 2011 Academy of Country Music Awards. Taylor Swift was one of the night's performers and winners, taking home the Entertainer of the Year award to close out the evening — see who took home all the top honors. Rihanna transformed her "California King Bed" into a duet with the help of Sugarland's Jennifer Nettles, and Ryan Seacrest cozied up with girlfriend Julianne Hough backstage. Nicole Kidman and Keith Urban were seated next to Carrie Underwood to watch the entertaining show, which had everyone from Steven Tyler to Celine Dion wow the crowd. Robert Pattinson and Reese Witherspoon came straight from their Water For Elephants press junket in LA and shared their sweet chemistry as they presented Miranda Lambert with one of her many statues. Reese's smile is also front and center in her wedding picture on the cover of this week's People magazine! Check out tons more photos from last night's rollicking good time!