I found this article interesting.
Hope the kid turns out OK health wise. It is easy to focus on the muscle bulk as a sign of health (and every thing may very well be ok down the road) but there may be some good biological reasons that myostatin is more regulated.
I think this has huge ramifications for athletics. Should folks who are double recessive (like this child) for the gene be able to compete with those that are only singly recessive (like the mother or father) or those that do not carry the gene at all? Wyeth is already working on myostatin blockers; if these are safe (unlike steroids) should competitive athletes be allowed to use them?