Crack open the champagne! Jay-Z hosts star-studded New Year party in Las Vegas as he's joined by Rihanna and wife Beyonce

By DAILY MAIL REPORTER Celebration: Rihanna takes over the DJ booth as she performs with a glass of champagne in hand, watched on by Jay-Z, at a star-studded party at The Cosmopolitan hotel in Las Vegas on New Year's EveThe champagne was in full flow as Jay-Z hosted a New Year party in Las Vegas which was bubbling with some of the biggest stars in the entertainment industry.Joining the rapper w...