You guys...
All clowning aside, I voted for real. I guess the whole sticking point for choosing one way or the other falls upon how you feel about the tools the workers are using. There are some who feel the tools that they're using seem quite antiquated, and therefore signal to the fact that they, the workers, are metaphorical.
On the other hand, there are those who are in the "If ain't broke, don't fix it" category and can accept that workers in the future might use some of the same construction techniques that we use today.
Count me in the "If ain't broke, don't fix it" category; I can accept the workers using construction techniques that are, seemingly, antiquated for a future time period such as the one we are witnessing. Again, "If ain't broke, don't fix it"... and, of course, the tools being used might have some sort of futuristic tech intigrated into them that we can't see.
Ultimately, I think the whole "Under Construction" tagline is served well simply by the fact that workers are working on the Enterprise. Their task is evident. I don't think the workers necessarily need to be from the past in order for that point to hit home, even if sound bytes from the past are used in the trailer.
