To those who believe in "infant baptism," it equates to a new believer being baptized into Jesus Christ, which removes any need for that infant (when they are grown and make a decision to give their lives to Christ) to be baptized upon salvation. Those that believe in infant baptism believe that the infant is, in fact, saved, and a Christian from birth. This is how I understand the comments they have made here, and other places as well.
Dedication of a new born child is widely practiced. It does not represent the child being cleansed of their sins, or receiving salvation, it is for the purpose of the parents promising to God that they will raise that child in His ways. It is a serious matter, for when parents have their new born child "Dedicated," they are actually entering into a Covenant with God.
Awhile back when I did the thread about "A Promise to God," some people raised a stink about such a thing. I wonder how many of them have participated in an Infant Dedication?
(edited)
I also did a thread "I Was Born a Christian" here on the BDF that addresses this very issue of infant baptism.