THe reimagined BSG is an excellent, excellent show. Tremendous depth, lots of excitement, and some great cinematography. They also have this tendency to come up with never-done-before cliffhangars that really keep me antsy for the next season. My favorite episodes have to be the two-part arc "Act of Contrition" and "You can't Go Home Again" in the first season, which proved beyond all doubt that BSG has no stock characters and that sci-fi can address deep themes without walloping you over the head with them, like Star Trek tends to.
(That said, TNG is one of the classic SF shows of all time. "Best of Both Worlds" absolutely rocked, and Q is just plain hysterical.)
I think "Firefly" also deserves a mention here...it was cancelled early, is a tiny bit cliched, and involves only stock characters (principled outlaw captain, genius kid mechanic, reluctant doctor, classic mercenary, etc), but the plotlines were fun and the dialogue could be downright hysterical.