What's the trick in creating popular web episodes like "Red vs. Blue"?
Well, first of all I can see that it's built on a very successful game. That would draw a lot of people if it were talked-up on the various game boards and such.
I'm using the pc game, the movies, for this web series. Will that help?
What you will need to do is talk it up on forums and blogs that are related to the series. That way people will find out about it.