Watching Firefly this week has made me think - science fiction seems to be going through some changes in the early 21st century. In the 70s-90s era science fiction was all squeaky clean Jedi, starship captains of "the finest ship/crew in the fleet" and so forth. Then by the 1990s things got a little darker - the Star Trek Federation actually had warships, Babylon 5 had religion, religious wars and invented mainstream sci-fi characters that had shades of grey.
Now we have shows like Firefly and BSG '03 that are very dark. Both are in the mainstream (BSG in particular, Firefly having done some weird phoenix thing by coming back after being cancelled at the 14 episode mark). Curiously Star Trek Enterprise and Star Wars both seem to be in trouble (though Episode 3 is going to be pretty dark and may redeem Star Wars if you believe Mr. Kevin Smith and it'll make money anyway).
Let's take Firefly as an example of darker sci-fi. The basic premise of the show is that the Millenium Falconesque ship Serenity goes from week to week going around space looking for jobs, legal or otherwise. It's a bit like someone made a TV series of the old computer game Elite in that respect.
The main character, Captain Malcolm Reynolds is a bit of a Han Solo type - brash, arrogant and frequently biting off more than he can chew he turns out to be one of those loveable scoundrels that'll rob you blind but never kills an enemy with a speaking part (not that Firefly lacked any recurring villains). He hangs out with his first officer Zoe, her husband the pilot, and a host of whacky sidekicks.
Or Battlestar Galactica '03 - a bunch of military nuts on a big boat with a bunch of civvies pretending they're in charge, with a bunch of sexy evil humanoid robots chasing them. Much politicing - much darkness.
By contrast Star Wars Episode 1-2 - a bunch of Jedi and Senators fighting to protect diplomacy and generally being polite to one another. No Han Solo type character to do the whole witty banter, only Ewan McGregor's Obi Wan Kenobi.
Enterprise - a rehash of the 60s Star Trek, missing the opportunity to use the grittyness of First Contact by making everything shiny and Star Trekky. The first episode showed promise, the second involved a nebula - surely a first in Star Trek - and I haven't watched another Enterprise show since then.