I read your reviews and I see some people have future cruises booked to the end of the next year. Is this price driven bookings or some other factors based? I am about to check cruise prices for December to compare.
Ships are going out full these days. If you want to be sure you get your preferred cabin on a ship, plan on booking 6 months or more. Europe started selling out last summer and I imagine this is true for NCL as well.
You can still find last minute deals, especially on Caribbean cruises. But not on holiday or spring break cruises. These sell out far in advance.
I've found that the best thing to do, like Anne said, is to book early, as cruising has become very popular! If the price goes down before final payment (watch the cruiseline's site) call your TA and they will get you the lower price.
Even after final payment you MAY get an offer to upgrade or some onboard credit.
Have a wonderful cruise, wherever you go!
"A truly happy person is one who can enjoy the scenery on a detour."