As a travel agent I have seen cruises leaving from US ports still high while a small downturn in the pricing of European cruises. Many of my clients book far in advance and the ones that recently paid their final payments the current prices are about double of what they paid.
In my own personal cruise, I booked it 3/1/15 for an April 2016 cruise on the NCL Dawn. For a family suite I paid $3150 for four people and if I book the same cabin today for myself it would be $6300.
Many people thinking that they are going to wait last minute for a deal will see not as many out there as many cruise lines are shying away from them. Royal Caribbean has announced no more last minute deals. Norwegian started last month that cruises booked under 30 days out cannot take part in their pick a perk promotion.