I'm not going to argue with people, and most people on my flist seem to have actually understood the episode (thank goodness). But, man, I am going to point out one thing, just in case anyone on my flist wants to argue with people in other communities:
Supernatural: the books =/= Supernatural: the show.
-There is a REASON the audience at the convention in the show was mostly dudes.
Also, if you really did want a commentary on how Supernatural's fanbase is predominantly female, I don't see how making them predominantly male in the episode is NOT making a comment about it. If they TRULY did not want to comment on gender and fandom, then they would have made the audience perfectly mixed. Think about it, people!
When a show does something you didn't expect it to do (or you don't agree with) a good course of action is to ask WHY they did it that way, rather than just complain. More often than not, if you think about it for two seconds, you'll realize that they had good reason to do whatever it was that they did.
Anyway...that's all I'm going to say on the matter.