I have to admit my first thought at 24 being brought back is renewed anger over Renee's pointless death in Season 8. That is still a stupid and pointless decision.
That being said, I'm looking forward to the show's return and having another open thread here on the boards. 12 episodes should cut the fact and best of all, the limited series will be written ahead of time. I didn't start watching 24 regularly until Season 7 but I've heard that the first 13 episodes of 24 were great because they were all written ahead of time. I heard the last 9 weren't as good because they were written after the show has been picked up for a full season.