Sitcoms are normally about normal people - the average person living in a big city (usually new york) and the kind of stuff most people identify with.
The big bang theory was a refreshing change in that most of the principal characters are geeks. It's based on how the lives of Leonard (Johnny Galecki) - an intellectual, nerdy and gentle physicist in Caltech and his roomate Sheldon (Jim Parsons) - possibly even more intelligent but antisocial and arrogant physicist who works in the same university, and the turn it takes when Penny (Kaley Cuoco) - a hot girl with an average intellect working as a waitress, moves across the hall from them. As expected one of them - Leonard - tries to establish a "relationship that might cumulate in coitus" while riddled with the typical geek shyness and awkwardness. To add to the fray are two friends of the roomates - Rajesh (Kunal Nayyar) and Howard (Simon Helberg) who are also wierder variations of the geek species.
I must say, that I was biased towards the show having been a geek myself and was both tickled and scared when I was able to identify too much with at least one very geeky thing in each episode. But the writing is pretty good, the context - while is something seen quite often in real life - is fresh for the small screen (with the exception of "Beauty and the Geek") and the actors all have excellent comic timing. Especially the character of Sheldon who grew up a child prodigy (a masters and two doctorates, but is baffled and disgusted by human relationships) is hilarious and is some sort of mix between a mad scientist and Mister Bean.
So far 17 episodes have been released as the first season (cut short due to the writer's strike) but it's been signed on for a second season. This show was one of my big finds of the year, and I'm sure this will be a hit with many of the geeks on this forum
