We just cruised the Spirit two weeks ago and the prices were the same as November's Pearl cruise as well. I used the Pearl as an example though because it was the same class of ship with more similar facilities.
I wonder if that was what that ship was charging when it was part of NCLA. Not sure but one thing that has been pretty consistent fleet wide are the prices in the speciality restaurants since we first cruised NCL in January 2005. Perhaps they've been doing some market research on the Jade lately. Things are changing rapidly with NCL since Apollo has entered the picture. I have to say I felt strongly service quality had improved on our last cruise when compared to our November Pearl cruise, and for the most part the Pearl's service was pretty decent.
Prices are creeping up though. Fuel surcharge has increased to $9 per day on NCL. Restaurants are increasing. Lots of daily activities for an extra charge, some have a lot of value. If they have the Martini tasting on the Jade and you can hold your liquor, it is a bargain at $15 pp. We had a ball, made great friends there, but unfortunately I cannot hang with the big dogs. We went to a few of these "tastings" scheduled throughout our two week repo cruise on the Spirit. The first time we "tasted" (drank) 6 martinis, the second one we "tasted" (drank) 7 martinis and the third one we had eight... I had to go to bed... it was not pretty. But they just tasted so good and went down so smooth. I am sure with your vast knowledge of the bar business, you will absolutely nail the martini trivia.
Hope you are having fun! Wish I was there.