I was just there (marrried 7.23.10 at RIU Palce Las Americas), and I have been to Cancun 3 times in the last 4 years, I have also been to Cabo, Puerto Vallarta, Cozumel....Cancun is the best by far, the best resorts and beaches. Believe me the people that choose to come to your wediing will be RAVING about the place. My coworker was married at the Royal 2 years ago, and she said she has never been anywhere more beautiful, she went to Domincan Republic for her anniversary and said she wished she would have simply returned to Cancun.