I'm siding with keeping the spoilers hidden too. Granted and I'll be honest I wouldn't mind being spoiled now since I'm one of those peeps that even when I read a spoiler about a subject, once I see it and hear it, and in this case, play it, I still get a good amount of shock value and new experience, but, for the best of everyone, it's only fair to wait until the 29th, or the 25th in Japan's case.
Edit: here’s the final battle trailer.
We feel too many things, now we’re gonna feel them all so all aboard the Feel Train!, CHOO CHOO!