I could never get into it, myself. The geek humour always felt too forced to me, and lacks the natural flow that it had in something like Spaced. It's all right for what it is, I guess, but I've never really understood why it's so beloved.
I watched the first season on DVD because my friends insisted that it was hilarious, and it was thoroughly mediocre. Then I watched the second season because they insisted that it gets much better.