tlogan was not saying SO was not valuable, he specifically said that it did not provide much value for experienced programmers. SO can still provide value to the masses of less experienced programmers out there and be extremely valuable.

In my experience I have found this to be true. When first starting out stackoverflow was crucial to my learning process, now it seems I've answered all of my own questions the last year or so. And I wouldn't even claim to be extremely experienced. Thus, SO has certainly become significantly less valuable to me, but I would have never gotten this far without SO.

I know. My point was that the fact that John Carmack was the one who said this suggests that he still finds it useful for himself, even though he is an experienced programmer. That is not conclusive proof, of course, just something to think about.

My take is that experience only lowers the value of SO for the particular platform(s) you have experience in. I've found SO very valuable in the last couple of years even though I'm (in general) not a newbie anymore, because I've had to build software for many different platforms like ruby, mac cocoa, ios cocoa, and windows (C#/WPF and C++).