I fully agree with the other replies in their interpretation of the term 'cabaret'.
On similar ships in the past we have had After Dinner speakers, a small production theatre/er show of Noel Coward's Private Lives, music "Tribute" acts, etc.
These ships do have guest lecturers, but they are usually scheduled totalk during the daytime on days at sea.
It is while off now, but we are travelling on Azamara Journey in August, so will give you a 100% factual answer after that - if I can find this post of course
Hope this helps,
Alan & Katrina
Last Cruise: Queen Victoria November 2014
Next: Queen Elizabeth December 2014
Followed by: Minerva April 2015