Eric Kripke: Mobilize Supernatural's fan army.

From here -- interview with Eric Kripke, containst potential spoilers.

MediaBlvd> Supernatural has always been up against very rough competition in its time slot. When you set up the new mythology for the finale, did you know that the show would be coming back for another season, or did you set it up with the hope that it would return?

Eric> We did not know if we were coming back. We were hopeful, but season three was not a sure thing, by any means. Quite frankly, behind the scenes, there was some fighting going on, to make sure we came back for season three. But, you can't let that affect your storytelling. I can't say, 'Well, I don't know if I'm coming back, so therefore, I'm going to wrap this up, or not wrap that up.' I just have to tell the story I want to tell, at the pace that I want to tell it, and hope for the best. Very shamelessly, that's why I want to get the message out to the fans. We have the best fans in the world, and I just want to mobilize that army. We want to come back for season four, but that's far more in the audience's hands and the fans' hands than it is in ours. So, tell your friends. I believe there have to be people out there who don't want to watch doctors banging in hospitals (like on Grey's Anatomy), or an endless procedural (like CSI).I know I'm in the minority of America, but I don't get those shows, and there has to be people like me. We're trying hard to live up to shows like Buffy and The X-Files, and we're trying to be a worthy show to these predecessors, and we think we're doing it. I just don't think a lot of people know that this show happens to be on the CW Network. We have a show that, in our opinion, is as cool as Battlestar, with an interesting and involving mythology, and we try really hard. We all care about the show and are passionate about it, we just happen to be on the same network as America's Next Top Model. But, tune in because we are there, and we'll have interesting conversations about [potential spoilers redacted].

(bolding is mine)