I have never told my child that Santa is real. He isn't so I would feel that I was being dishonest. I always told him that he was just like Barney, Winnie-the-Pooh, or any other made up character.
Besides, I never wanted Santa to get credit for the money I spend on my child's gifts.
However, he did get to sit on Santa's lap and take pictures. We do have fun at Christmas time.