[Will]

My take on the cancelation: it's ok. SG-1 jumped the shark a while ago. You could debate the moment when that happened, but you would have a hard time convincing me that it hasn't. So, it took what, 8 seasons to turn the threat of Gou'ld invasion into a basically non-issue, do you really want to repeat the same process for Ori? And where do you go after that? The time has come, I think, for it to end.

I think the entire model of the show is just about done, as well, so Atlantis will probably only last a few more seasons. Like alarikf said, it's very much in the Star Trek and Quantum Leap models. While it can be good, there comes a point when you've already tried out a bunch of different places, and anything else you do will end up seeming like a contrived re-hashing of previous episodes.

Where sci-fi in general is going, I think, is away from shows in the Star Trek mold, where everything is "perfect", and nobody really has personal problems from episode to episode beyond the obligatory romantic/sexual tension, and replaced with stories like Babylon 5 or the new Battlestar Galactica, where there are humanized characters with actual problems like addiction, depression, long-running feuds in the forefront of the story, "good" characters doing "evil" things, "evil" characters taking the high road and doing "good" things, etc. In other words, shift the focus of the story to characters with a scifi background, instead of a scifi environment populated by relatively flat characters.