I believe Clannad After Story is only going to be 24 episodes, and its already at episode 20 or so. And yeah, Haruhi season 2 is probably the show im looking forward too more than just about anything else (other than a possible continuation of FMP that is lol)
21 of After Story is the latest. 22 is the last episode of actualy story, 23-24 are supposedly extra episodes like the Tomoya X Tomoyo alternate episode from the first season.
As for Haruhi season 2: Can't wait! Can't wait! Can't wait! Though I'm sure you're with me in that boat.
What's starting in April is actually Haruhi (the original series) going into syndication. Sorry to disappoint any fans but it was initially reported as as a new series but was later corrected by Kyoto Animation and Kadokawa Shoten. Haruhi 2 has disappeared from ANN as well and we're back to square one. Ironic since the title of 2nd book is something like The Disappearance of Haruhi Suzimiya.
There are some original net animated shorts out though from the franchise. Haven't watched them though.