The preorder said Q4 2011. They changed it?
The release date is a place holder, not a fixed date... better a game company who somehow delay a release that a one who rush for meet a release date... usually, rush mean almost unplayable game filled with a lot of bug... today, it is the actual trend for a lot game company but not Stardock... They have test first hand what can be rushing with some of their other game titles...
Since people who have pre-order Rebellion will be able to beta test the game, the Q4 2011 is somehow a valid date for them... if the game is planned to be released spring 2012, it mean that soon the beta testing phase will begin...