It can also depend on the port and passenger demographic, for example non-US pax can delay the whole process if they haven't been cleared prior to arriving in a US controlled port, or nationals from some countries are not permitted to go ashore in other regions.
But for the normal day to day events, Donna's answer has it all.
Last Cruise: Azamara Journey August 2014
Next: Queen Victoria November 2014
Followed by: Queen Elizabeth December 2014 and Minvera April 2015
Golden, Grand(2), Caribbean, Sea(4+1 aborted)
Adonia(4+2), Arcadia, Artemis(2), Aurora(5), Azura(2), Oceana(3), Oriana(11), Ventura(2), Victoria(5)
QM2(2), QE2(9), QV(5), QE, Caronia(2), Minerva II, Fred.Olsen(8), NCL Jade, =X= Eclipse, HAL Ryndam, Aza.Journey