We definitely will have that argument when the book is actually released. With that being said, Milo ≠ Brietbart. He certainly has shown to be a bit biased in other arenas, and perhaps in this one as well, but to say that our current sources do not include bias already would be inaccurate as well. He has also shown to be a very accomplished journalist in his own right independent from this. Sure, many of his pieces may not be WP standard, but that's not what I'm saying. There are biases on both sides, so disqualifying a source just based on real or perceived bias would leave a very barren article. 
 ::::: As for Avono's point, let me ask this: Would it be WP:NOR for an editor to bring a scientific study that is ostensibly not about Gamergate, but which might prove or disprove something that is on this page (i.e., if a study that said video games do not cause sexism, would such a study be appropriate on this page?)