I don't see what the problem is with the post. Don't get me wrong, I'm just as pro-GLBT as any other guy, and I'm definitely not a stranger to anime or cosplay. That being said, I still don't see what the problem is. Operating under the assumption that this was a humorous title by Alex (and this is the basis for my entire opinion) there isn't anything wrong with the title. He pointed out that the males (who are referred to as males, not as transsexuals) appear to be ugly females at first glance. This is a reasonable statement - not one that is inherently nice, but reasonable - as I'm sure that anyone would think the same thing unless they were intimately familiar with this sect of cosplayers.
So really, if the 'ugly-chicks' title isn't offensive, then the only thing left is his use of 'chicks' and 'dudes' instead of male and female (or women, or womyn). Personally, I have used 'dude' and 'chick' for years to refer to my peers and contemporaries, and see nothing offensive with his use of them in the post. I understand that these terms can sometimes be used in an intentionally derogatory way, but I do not believe that that was his intent.