10. Stargate: My favourite version is Atlantis but SG-1 is also quality and Universe is a little sloppier but I like the show on the whole and particularly the science fiction elements and the characters were memorable.
9. Merlin: I came to love the family friendly nature and characters of the show more than anything. The whole Camelot link was just ridiculous to be any true Arthurian kind of thing, but it had its moments (good and bad).
8. Once Upon A Time - I like a show with interesting plot twists and arcs, fun characters and devious villains. I found all of that in this show - particularly in Rumpelstiltskin
7. Primeval - It's a show that starts off slowly but has very memorable characters and some very good effects and storylines going for it!
6. Firefly - Cut down in its prime and with weird, wacky and different sci-fi ideas to anything else.
5. Avatar: The Legend of Korra - A nice sequel to the original animated show which expands the world and creates some interesting new characters (particularly villains).
4. Doctor Who - Classic sci-fi television, how could it not be on my list?
3. The Clone Wars - Star Wars junkie here, and as for how shows go? This has some of the best sci-fi story telling and Star Wars stories around. It strengthens up a set of flawed sequels, adds new ideas into the mix and messes around with deep ideas (and it's a children's show)
2. Sherlock - Perhaps the best that the BBC is producing at the moment with the quality of each episode like a short movie and with some incredible acting performances.
1. Avatar: The Last Airbender - One of the best animated shows around and easily my favourite show. The attention to detail, to world-building, to character creation is incredible and again it's aimed at children. Which shows that you don't have to target the 'adults' to make brilliant stories.
Agents of Shield - I happen to love anything Marvel related, so a whole television show focused around S.H.I.E.L.D had me hooked from the thought. However the execution is not quite as smooth as it could be. Still a fun show!
Avenger's Assemble - Another animated show which is very high quality viewing and unfortunately was cut in its prime. I could say the same for Young Justice or Batman: The Brave and The Bold though...