Many people here at the forum, and generally, have asked when is a photo of naked child acceptable and when is it not? Well, it's obviously always going to be a grey area. It's a little like when is slapping a child harmless discipline and when does it become child abuse?
From my point of view, I think a picture of a nude baby or child is, generally, kind of cute and harmless. But if you don't feel it belongs in the family photo album; if you don't think it's suitable to display on your mantle piece, or if you're not comfortable showing it to grandma, then quite possibly the photograph shouldn't have been taken in the first place.
Oddly, a number of people here have jumped on the pro pornography wagon, but isn't this really more about protecting children and their innocence rather than protecting adults' rights to view porn?