Ashley Tisdale and Julianne Hough slipped into another set of bikinis and hit the beach in Miami yesterday. The girls are hanging out in the Florida city where Julianne has been working on Rock of Ages, and Ashley is visiting her boyfriend Scott Speer on the set of Step Up 4. Ashley tweeted a big thanks to Julianne for including her on "all the fun stuff" while Scott is off working. Julianne and Ashley had a bikini jet-ski adventure over the weekend with Derek Hough along as well. Some of Julianne's Rock of Ages costars, like Tom Cruise and Alec Baldwin, have already finished filming on the movie, but she and director Adam Shankman are still toiling away in paradise. The location has certainly given Julianne an opportunity to perfect her tan, and both she and Ashley are going strong in our celebrity bikini bracket — make your picks for a chance to win $1,000 to J.Crew!