Today on Twitter, Jennifer Hudson shared that she's going to have the best 30th birthday ever. On September 12, she's going to perform for Aretha Franklin! Also in today's tweets, Britney Spears announced the idea for her 'Criminal' music video, while Nick Jonas continued to tease his followers that he's got "big news." The rest of the pop stars spent their day goofing off -- Christina Perri got a sign from the King of Pop, while the Ready Set mended his goose bite wound and Weird Al shared a photo of his new Justin Bieber toothbrush. See what your favorite stars were tweeting today!