I know there are some here that would disagree, but I don't feel Enterprise was ever a quality series. The writing is not of the calibur of earlier Star Trek series, the characters are not interesting and they keep finding new excuses for T'Pol to get naked (which I grant you is fun to watch, but is really a mark of desparation to get people to tune in).
In my opinion, Star Trek reached its zenith with Deep Space 9 (the best Trek ever, bar none) It managed to remain better than average with Voyager (after its second season), but then it jumped the galactic shark with Enterprise.
The show will probably be canceled because no one wants to watch it. No network in their right mind will consider picking it up. Enterprise is truly the series that boldly sucks where no show has sucked before.