My own thoughts:
I wonder how much "hundreds of blog posts written by one man" is the true rejection. I mean, would the reaction be different if it was a book instead of hundred blog posts? Would it be different if the Sequences were on a website separate from LessWrong? -- The intuition is that a "website by one man" would seem more natural than a "website mostly by one man". Because people do have their personal blogs, and it's not controversial. Even if the personal blog gets hundreds of comments, it still feels like a personal blog, not like a movement.
(Note: I am not recommending any change here. Just thinking loudly whether there is something about the format of the website that provokes people, or whether it is mere "I dislike you, therefore I dislike anything you do".)
Having peer-reviewed articles (not just conference papers) or otherwise being connected with the scientific establishment would obviously be a good argument. I'm not saying it should be high priority for Eliezer, but if there is a PR department in MIRI/CFAR, it should be a priority for them. (Actually, I can imagine some CFAR ideas published in a pedagogical journal -- that also counts as official science, and could be easier.)
The cultish stuff is the typical "did you stop beating your wife?" pattern. Anything you respond... is exactly what a cult would do. (Because being cultish is an evidence for being a cult, but not being cultish is also an evidence for being a cult, because cults try to appear not cultish. And by the way, using the word "evidence" is an evidence of being a brainwashed LW follower.)
What is the relation between politics and skepticism? I mean, do all skeptics have to be perfectly politically neutral? Or is left-wing politics compatible with skepticism and only the right-wing politics is incompatible? (I am not sure which of these was the author's opinion.) How about things like "Atheism Plus"? And here is a horrible thought... if some research would show there is a non-zero corelation between atheism and a position on a political spectrum, would it mean that atheists are also forbidden from skeptical movement?
I appreciate the spin of saying that Julia is just a pretty face, and then suddenly attributing this opinion to LW. I mean, that's a nice Dark Arts move -- say something offensive, and then pretend it was actually your opponent who believes that, not you. (The author is mysteriously silent about his own opinion. Does he believe that Julia is not smart? Or does he believe that she is smart, but that it is completely accidental to the fact that she represents LW on Skepticon? Either choice would be very suspicious, so he just does not specify it. And turns off the comments on youtube, so we cannot ask.)
If it was a book, it'd be twice the size of Lord Of The Rings.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.