Battle Star Galactica
Wow. This is the BEST sci-fi I have seen on television since....? I can't recall. They manage to weave human drama, cutting edge camera/fx work and superb story-telling consistently week-after-week. If you like sci-fi (or even if you don't), do yourself a favor and record/tivo this. Be sure and check out the episode MP3 commentary podcasts.
Btw, I am not commercially associated with the SciFi channel in any way. Just a fan of this show (an extreme rarity for me).