I love the Bellagio during the holidays. They always do a great job decorating for the season.
You can walk the shops, around the casino, or at the registration area and take in all the beautiful decor.
Now keep in mind, we are in Vegas, so there is always a crowd... Even more so on Christmas day which can make getting around a little tough. But I do love walking around listening to the music and looking into the stores, into the Jean Philippe shop! Can we all just hum YUM together... Yyyyuuummm!
No matter what the season if you're in Vegas, take a stroll through beautiful hotel/casino.