John_S:
OK guys and gals, thanks for your input!
We've had a conflab here in the office and come up with a top-five list from your suggestions:
Battlestar Galactica (the new one - no, not Galactica 1980. That was awful)
Star Trek: TNG
Red Dwarf
Dr Who (the rebooted version, from Christopher Eccleston onwards)
Thunderbirds
Weird, I don't remember anyone mentioning Thunderbirds?
Why these? Because we reckon they all represent some sort of watershed moment; they all had massive prime-time success, and all got non-sci-fi fans talking about them.
Others, such as Firefly and Stargate SG-1 came close, but we thought they were a bit niche for this list.
Hmm, DS9 got a lot more comments than anything else from what I can see, it wasn't massively mainstream (in this country anyway), I admit.
So - these are the five to choose from. Pick your winner!
What's the criteria again? Just our personal favourite, or most influential or what?