Looking at the Pride of Hawaii's remaining schedule, and the Norwegian Jade future schedule, there isn't much time for a wet dock in Honolulu.
Pride of Hawaii
7-Day Hawaii, Round-trip Honolulu
2007: November 5, 12, 19, 26; December 3, 10, 17, 24, 31; 2008: January 7, 14, 21.
12-Day Hawaiian Escape, Honolulu to Los Angeles
2008: January 28.
Note: There is a 6-7 day gap in Los Angeles.
13-Day Panama Canal, Los Angeles to Miami
2008: February 16
Note: There is no time gap while in Miami.
13-Day Transatlantic, Miami to Barcelona
2008: February 29
Note:: There is an 18 day gap while in Barcelona.
12-Day Classic Mediterranean, Barcelona to Istanbul
2008: March 30.
Therefore, the wet/dry docks probably occur in California and Spain. No ship is left idle, out of service, intentionally for 6 to 18 days unless the ship is in a shipyard for refurbishment and maintenance.
I expect a wet dock in California for the crew changeover and inspections for changing the flag. I expect more maintenance and refurbishments will be performed once it arrives in Europe. I'm not sure 6-7 days is long enough to remove cabins on Deck 6 to install a casino while the ship is in California. But if it is, there will not be much time to do much more.
I don't know which shipyards are scheduled to do the work.