Is there a Santa Claus?

So this is Little John's first Christmas that he'll remember (he was only 2 and 1/2 months old last year) and I've started thinking about the whole Santa Claus thing. I really want to teach him the nativity story and go from there with something along the lines of "and just like the kings gave baby Jesus presents we give each other presents, because we love each other and to remember his birth" and then I want to go farther with the story of St. Nicholas- the nice old guy who gave kids toys to play with and coal to keep warm. And then to go on from there with thats why there's all the nice stories/movies about santa, but he's just a nice make belive name we use to give present with out saying who gave them like a secret suprise. And then to bring it back to love and family and Christ.
But... I don't want to squash the magic of the suprises from santa, and I don't want to be the mom of the kid who goes around crushing other kids dreams by saying there is no Santa.
But... I don't want him to get all into the "Santa will get me anything I ask for" and thus get caught up in the "gimmes" at Christmas and miss the truth of it all.
Maybe its too soon to worry about this, but you set patterns early on and whatever we do with Little John we'll have to do with the rest of them. Any ideas from the other parents out there?