Just returned from the Cloud on 9/23, Stockholm to London. While I could not see any of the male guests in white diner jackets, many of the senior staff wore them. The primary reason I would not go for a white dinner jacket is that they show any minor stain so badly. That is why I dressed in a black tux.
By way of a funny story, I was worried about what shoes to wear with the tux. (Here in Oklahoma, we don't wear them often!) Then, a few days before my cruise I was at a political party and met one of the "stars" of the TV show called "Queer eye for the straight guy." (Note: I did not chose the name of this show. I would have called it "Gay eye for the straight guy.") In any event, this guy was one of the clothing experts on the show, and recommended I wear cap-toed oxfords with a spit shine on the caps. On the cruise, I found his advise to be exactly correct.
Thanks,
Richard