@matana
Now I'm just waiting to see where in his post is the fallacy. Cause in his argument, the "countless cases" aren't people believing an idea/hypothesis/theory. They are examples of successful predictions/explanations of a certain model.
And you claiming there's a fallacy in there, is like saying the theory of gravity is just "Argumentum ad populum" if it's successfully used to explain how people end up falling to their death (instead of flying) if they jump off roofs.

Now, if you have evidence that contradicts the theory/model he's talking about, that fine. Present it to whoever is interested to hear it. But considering how badly you bungled up "Argumentum ad populum", I'm not gonna be one of them.