The IT Crowd, sketch show Modern Toss and Peep Show will also return.Link (Thanks, Stephen!)
(Disclosure: I was an unpaid consultant on series one of The IT Crowd, and my fiancee works at Channel Four)
Previews of IT Crowd episode six
IT Crowd, season 2, episode 5: the boob joke episode
IT Crowd Season 2, Episode 4 -- and DVD!
IT Crowd Season 2, Episode 3: Great anti-piracy PSA sendup
IT Crowd Season 2, Episode 2 -- keyboard-destroying nerd sitcom
The IT Crowd -- season two, episode one