We may wonder if Rockets were going to appear in the episode N from the start or not, but I guess most people were surprised they were going to return this fast, as many fans were betting that they're done for BW and they return for 6th gen. But what matters more now is the fact, that their comeback was made to be something big. Even if some people might have thought that they could be back after league, but I think we all egreed that it wouldn't be anything big. But instead something opposite happened. Of course, we haven't seen Episode N yet and we may only guess what may happen, but many signs show that their role may be increased to what they had so far. I don't think it was decided to be this way randomly. And no way they could decide this in the early 2012... Why? Because I'm pretty much sure that it's thanks to the Rocket radio's popularity (which started in July). It was said in the radio's finale ep that it's thanks to fans that Rockets make a "full return" to the anime, so I guess it pretty much speaks for itself.