I dont see why kids can't enjoy believing in Santa. I still remember one child ruining it fir us all because her family didn't do Santa.
In saying that my DS also knows that we are celebrating Jesus' birthday.
I don't think there is anything wrong with kids enjoying believing in Santa but I also don't think there is anything wrong with not doing Santa at Christmas time either. I think each family needs to work out their own traditions that they are happy with. I think too, most of us that don't want to make Santa into a big deal have expressed a fair bit of concern about making sure that our kids don't spoil Santa for families that do want to celebrate Christmas with Santa. It's just not for everyone.

I don't think for most people in this thread it is a case of Jesus Vs Santa, I think everyone has different priorities at Christmas and for some neither of those things are important and they just see it as a time to celebrate with family.