This is discussion archived from a time before the current discussion method was installed.
Red Shoe: If my memory does not deceive, it seems like there was a period during the 80s when, rather than On the Next, they would show this promo at the beginning of the episode, as in "Tonight on Knight Rider..." (that being the specific example I recall). As these are always removed in syndication, I have no way to confirm this.
Corvus: Space 1999 did that as well. Often the promo made as much sense as the actual episode.
Red Shoe: And now that I think about it, the original Battlestar Galactica — which I suppose is paid homage by the montage titles in the new series.
Furthermore, it seems to me like just this past year, the On the Next have started cheating. The West Wing in particular seems to be showing clips not just from the next episode, but from episodes two and three down the line.
Drop Dead Gorgias: I feel like a lot of shows, particularly in the season premiere have an "On the Next" that spans several shows into the season. The voiceover is slightly different too, it's like "Don't miss the action this season on the OC." Other than that it's like a normal On the Next.
Red Shoe: Thing that annoys me: The past season or so, the "On the Next" for several shows (most notably Gilmore Girls) shows the very last line of the next episode, which is always something totally unrelated to the plot of that episode, but really a teaser for the next episode (if you follow). For example, the penultimate episode a few seasons back showed Lorelai asking Luke to marry her as the On the Next. This happens at the very end of the episode, and she asks him more or less entirely out of the blue; it's not connected to anything else in the story. It's not until the episode after that (which was also after the season break, of course) that it becomes relevant to the plot.
Vampire Buddha: Following this thread
in the forum, Post-Episode Trailer now redirects to On the Next. 