Dax Shepard

Los Angeles, New York, and England were prime filming spots for celebrities this week. Matt Damon, George Clooney, and Bill Murray proved how good they look in uniform on the set of The Monuments Men, while a pregnant Maya Rudolph joined Joaquin Phoenix on the set of Inherent Vice in LA on Tuesday. Meanwhile, Cameron Diaz rocked a fake baby bump in NYC, and across town Emma Stone was swinging around with Andrew Garfield on the set of The Amazing Spider-Man 2 on Monday. Click through to check out who else was hard at work this week!

Kristen Bell hit the red carpet alongside fiancé Dax Shepard for the CMT Awards in Nashville, TN, on Wednesday night. It was Kristen's first public appearance since giving birth to daughter Lincoln in March, and she made sure to show off her postbaby figure in a short leather dress and sky-high heels. Kristen returned to host the show for the second time with country singer Jason Aldean.

Also on the red carpet for tonight's big show were Taylor Swift, Nicole Kidman, Keith Urban, and Carrie Underwood, who posed sweetly with her hockey-player husband, Mike Fisher. Carrie hit the stage to perform a tribute to the Oklahoma tornado victims accompanied by a full choir, as well as photos of the aftermath from the devastating storm that hit her home state late last month. Sheryl Crow, Kimberly Perry, Lisa Marie Presley, and AnnaSophia Robb also made appearances on the carpet before taking their places inside.

Kristen Bell and Dax Shepard posed for photos on their way into Nashville's Bridgestone Arena for the CMT Music Awards this evening. It's a big night for Kristen, since she's hosting the show for the second time and making her first official appearance since giving birth to daughter Lincoln on March 28. Kristen will be joined on stage by country star Jason Aldean, and the duo got together earlier today for rehearsals. She's been sharing behind-the-snaps of their preparation on Twitter and also joked about wearing "treacherous heels" since she'll be standing next to Jason, who is over six feet tall. For the red carpet, though, Kristen chose a more sensible pair of heels and a sexy leather dress, while Dax dressed up in a neutral-colored suit.

Twitter officially rolled out a Vine app for Android users today! After launching earlier this year exclusively for Apple devices, Vine has quickly become one of the newest social networking apps to take the world by storm, and celebrities from all over are jumping on the video-sharing bandwagon as well. From Tyra Banks's goofy makeup-chair videos to Victoria Beckham's fashionable clips, stars have proved that they are just as obsessed with Vine as we all are. Click through for our favorite celebrities to watch, and be sure to follow POPSUGAR on Vine!

Yahoo is scooping up Tumblr for $1.1 billion, gaining 108 million microblogs in the process. Just like Instagram, Twitter, and Facebook, Tumblr is another way for celebrities to connect with fans. And since they have more creative control over the sites, the content is often a more authentic and sometimes edgier expression of the celebrity's image. Pop icons like Beyoncé and Britney Spears use the site, as do TV stars Zooey Deschanel and Aziz Ansari and fashion insiders Terry Richardson and Rachel Zoe. As Tumblr makes big news, check out the top celebrity Tumblrs you should have on your dashboard.

Kristen Bell and Dax Shepard ventured out of their LA home and headed to brunch with their newborn daughter, Lincoln, on Sunday. The trio's dining excursion marked the first time we've seen Kristen and Dax out with Lincoln following her birth on March 28. Dax admitted to only having left the house twice since then, when he stepped out to host a CASA of Los Angeles gala last week. Kristen will soon be the one in the hosting spotlight after it was announced that she'll return to the stage for the Country Music Television Awards in June. It'll be her second time heading up the show, though her cohost has yet to be revealed.

Kristen Bell and Dax Shepard welcomed a baby girl and shared the news on Twitter yesterday. The couple, who have been dating since 2007 and got engaged in 2009, named their daughter Lincoln Bell Shepard. The couple has had many sweet moments through the years, and we're taking a look at some of the best to celebrate their exciting new addition!