South Park series 10 - Out a fortnight ago
Thick of It Specials - Out last week
Time Trumpet - Due next week
Stewart Lee's Comedy Vehicle - May 18th
Peep Show Series 6 - August, so I guess it can't be far off now?

Also, Fopp have some excellent deals on right now:

Complete Black Books - £8
Complete Spaced - £10
Nighty Night - each series £5
Complete Green Wing - £15 (or thereabouts)
Garth Merenghis DarkPlace - £4
Brass Eye - £5
First 4 series of Peep Show - £3 each

Comedy's great, isn't it?