If Cruise was there for only one day it is unlikely he is in the movie. Unlikely but not impossible. Let's just hope not.
Of course, because as we all know, Trekkies are the most self-righteous and snobbish when it comes to the Trek name they think they own, and big name actors are just the worst thing that could ever happen to Trek.
That's why when there was all this Gene Hackman talk, they made the right choice with Anthony Zerbe. And who needs Sean Connery when you can have Laurence Luckinbill?
And how many days do you honestly think it look to film all those 30 second cameos per actor for the last Austin Powers movie?
I would not object to a "big name" actor, just Cruise. He carries too much baggage and would be a distraction. As I mentioned before, Ron Howard refused to give John Travolta a part in Apollo 13
for much the same reason. Any scene with him in it would be like "Hey! There's John Travolta!" and it would detract from the film. Travolta practically begged
Howard for a bit part in Mission Control but Howard refused.
Oh, and if having a bit of taste makes me "self-righteous and snobbish", well so be it. Somebody has to hold the line on quality. That's why we have movie critics and fanboys.