We won't be doing it. We've decided that we don't want to make our kids believe in something that isn't real. My parents really laid it on thick with the Santa thing with my little sister...and she believed it 100% until she was about 12. When she finally realized he wasn't real, she was really devastated and was upset for months that our parents had lied to her all her life. I don't want that to happen to my kids.
We'll probably still play at these things, but only as long as they know that Santa, the tooth fairy, Easter bunny, etc are not actually real people/beings. I want the holidays to be fun for them, but not at the expense of their trust.