Paramount has canceled Star Trek: Enterprise right at its high point. The writers this year have been systematically dealing with every single problem ever raised by critics against the series. They have written a few absolutely incredible multi-part stories after a pretty good season-long arc last season. They've tied the show into the original series in ways fans had originally hoped would happen but never did until now. The character development has tremendously improved. Most importantly, the stories this year have been some of the best of the entire franchise. I've liked the show all along, but it took until last season to get really good, and the non-filler stories this year have been some of the best Trek ever. It's not quite up to the final ten-part season finale for DS9, but the only things that high up the scale are Babylon 5 and the best episodes of the two Stargate series.
Paramount made one mistake. They moved the show this year to Friday, the night that they knew the SciFi Channel runs the most popular science fiction show of all time, Stargate: SG-1. They even play it at the same time. Since the Stargate shows show in the summer and spring, the Paramount execs had an entire fall to realize that they were going to be competing in the spring with the most popular show ever to air in the genre of their show. The one piece of information they cite for why they're canceling the show is that it got low ratings, especially low in the first week of the complete SciFi Friday lineup on the SciFi Channel. Unfortunately, Paramount owns both the show and the network, so it's not even clear that another channel could run it if another one could be found to run it (though SciFi themselves might do so if given the chance; they're willing to run the complete tripe Andromeda has turned into). [Hat tip: Ramblings' Journal]