Ah, DS9, the poor, misunderstood middle child of modern Trek incarnations.
For a show that allegedly GNDN, it managed to accomplish the following things:
Introduce religion, or perhaps more properly faith as a viable motivating cultural force in the created Star Trek reality. Previously in Star Trek, it had been mocked and sneered at, called myth and mysticism, strongly implied that a culture with a strong sense of faith was somehow inferior to the rational-to-a-fault United Federation of Planets.
Portray a realistic, loving relationship between a father and son in Benjamin and Jake Sisko.
Portray a realistic, non-sexual friendship between Sisko, male, and Jadzia Dax, female (well, most of the time).
Show us that, unlike every other Trek show, one's decisions do have consequences. In other words, the show managed to avoid the dreaded Reset Button syndrome.
Wasn't afraid to confront the fact that a Klingon as portrayed in the 1960s looks different from a Klingon today.
Managed to make the Ferengi tolerable, once in a great while.
Oh, yeah, and for a show about a place that just sits there it managed to make the space station a strategic flashpoint in a Cold War with The Dominion that eventually turned hot and embroiled over three quarters of the entire galaxy, effected real political change in just about every major power in the Star Trek universe, actually managed to promote its officers from time to time (Will Riker has held the rank of commander for how long now? Nearly fifteen years??), and transformed the lead character from a wooden, gloomy man obsessed with his wife's death to a vibrant capable leader and religious icon who ended up as a creature who is not shackled to the bonds of linear time.
Yeah, it was a pretty boring television show, all right.
Update 14-Jul-2001
It appears, with the advent of the newest Trek spin-off called Enterprise that the powers that be at Paramount Studios have no clue what to do with the post-DS9 universe, electing instead to go back in time to pre-TOS days. Sigh. We could have had the struggle for galactic unification ... extragalactic exploration ... all kinds of good stuff. Instead ... we're still stuck with Klingons and Vulcans. Sigh.
27-Mar-2002
Okay, so sue me, I actually think Enterprise shows a lot of potential, thanks mostly due to Scott Bakula and Linda Park. Also a certain noder works on the show. Don't want to piss them off, do I? ;-)