That's not being fair, that's being contrary. If StackOverflow was a stupid idea or poorly executed, no one would use it. Yes, they announced it from a pretty tall pulpit, but if no one cared what either of them had to say--for or against--no one would care to read their blogs, either.
Sure, it's being fair. Before we go off and pronounce that "Jeff Atwood has proven everyone wrong," let's keep a few things in mind. Also, having a lot of readership does not prove someone is a top shelf programmer.
To be honest, this is not even something that Joel and, perhaps, Jeff haven't said themselves.