John Carmack is the definition of a programming god, imho...so usually, when he says something about programming, I usually say...okay.
You have got statements from the David Shippy, then you've got comments from John Carmack...so unless somebody is a programmer, and they have some pretty robust data to back it up...I kinda have to believe what those guys have to say...over some fanboys screaming "Cellz Rulez"