Lepus, one of the problems with Firefly has been that Fox has had no idea whatsoever how to promote it: "meet the most spaced-out crew in the galaxy." Yeesh. No wonder you thought the ads were cheesy. As for Buffy, well, tastes differ, but I will say one thing in defense of Buffy that people who've never seen it have a hard time believing: It avowedly is not a simplistic teenybopper show. It has some genuine depth behind the surface silliness (and the surface silliness is one of the things I like about it).
But that's neither here nor there. I'm really glad you enjoyed Firefly. Thanks for checking it out. Interesting that you enjoyed last Friday's episode, since among fans it's being said that this would be one of the least accessible eps: one where if you don't have the backstory from previous shows, you'll be at a loss to know what's going on in the story. Glad that wasn't the case. It was my favorite so far; I especially loved the philosophical bounty hunter, and River "posessing" the ship.
Now, the bad news: the day before that episode aired, Fox informed Mutant Enemy (the actual production company) that they wouldn't be ordering any more episodes, effectively cancelling it. The original pilot will air this coming Friday, and then that's it, unless Fox decides to air the three remaining eps that'll be in the can (they actually wrap tomorrow) later on.
But Joss Whedon is trying to shop it around to UPN (and maybe others), and it sounds like there's a halfway decent chance it'll get picked up elsewhere, in which case there'll already be three episodes available to show as they gear back into production.
Hope springs eternal.
p.s. Yes, Ron Glass is one of the best things about Firefly. What a marvelous acting job he's been doing there. Mind you, in my book, Barney Miller is still the best comedy to ever appear on American TV. But a half-season of Firefly has me so that now, when I think of Ron Glass, I think of Shepherd Book, not of Det. Harris. He's really the character about whom there are the deepest mysteries, which were demonstrated nicely in the show you saw, Lepus.