well im up to date with The big Bang Theory. for some reason i find is necessary to compare it to The IT Crowd. The Big Bang Theory has very funny jokes, and is more realistic, and uses real world references, as opposed to The IT Crowd, which is a bit more slapstick. also uses made up things like "friendface" where The Big Bang Theory actually mentions things like twitter, ubuntu, etc... Yes The IT Crowd does make some real references too, but not as much. it seems like the writters for TBBT know more about the tech world the the writters for TITC.
that said i come to my conclusion of
The IT Crowd > The Big Bang Theory
why you ask? for one simple reason. almost every single episode of TBBT is about relationships and sex and awkwardness. blah blah blah. its like American Pie for techies. its still a good show and ill still watch it but
LONG LIVE THE IT CROWD.