There is no doubt about who reigned the Billboard Music Awards in Las Vegas last night! Teen pop star Justin Bieber scored a whopping 8 trophies, while Eminem landed 6 and amongst them the most prestigious honor of the night, Artist of the Year. Taylor Swift, Lady Gaga, Katy Perry, Rihanna, Taio Cruz & Train didn't do too shabby either. Check out which awards they were all honored with by clicking through the gallery.