I would agree and say if you have a specific cabin you are looking for - book now. Also, if you are looking for a family suite, does that mean you will have more than 4 in your cabin? Book now as well if that is the case. Sometimes the rooms that accommodate the larger parties book sooner than later.
Heck, we booked our Feb. 2003 cruise last March, and before this week is through - we will have our Feb. 2004 cruise booked!