I spoke too soon--volume four of Bakemonogatari, which originally was slated for December 23, will be pushed back to January 27. Subsequent releases are all being pushed back by a month. Volume 5 will street on 2/24 and volume 6 on 3/24.
What makes this piece of new interesting is that episode 10 of Bakemonogatari, the conclusion of the Nadeko Snake story arc, is suppose to be improved in the home video release. The TV broadcast for that episode was filled with scenes that were either missing or still shots, and was source for some controversy.
Before all of us put on our pessimism hats and assume that this delay was related to SHAFT fixing it up, there are also the web-broadcast episodes we're all waiting for as well. Recall the first episode was pushed back one time already. Looks like they have their hands full! It can't be fun to put out a press release within 24 hours of seeing the good news about how well the thing sold.