Here's a great article out of the Yahoo travel department. It lists 10 top tips for getting a room upgrade at your hotel. #1 is for our honeymoon couples. If you're interacting with the hotel management in advance, by all means take the opportunity to mention that it's your honeymoon. It's a lazy staff that won't at the least mention it when you arrive or have flowers or a bottle of wine in your room. If you don't get the opportunity to mention it in advance, then do so when checking in. Of course, if you're registered at Smart Honeymoon, then you can use your Smart Honeymoon debit card when you check in to get instant honeymoon recognition.
Good luck and happy honeymooning!!!