To be clear - entertainment isn't a big deal to me personally, but because I come from an entertainment background and because I know some of our readers like it I do make a point of reporting on it.
My personal opinion is that cruise ship entertainment could be better, in most cases. NCL has great entertainment. Oasis and Allure also do.
I am usually happier if the ship has a movie theater and good in-cabin TVs. One of the things that makes the Solstice class so special is the large flat screen TVs.
Azamara had a smaller TV, but they showed recent movies all the time and gave us an accurate movie schedule - that is something a lot of ships can't seem to do.