What if J.K. Rowling was having a pre-book six interview like this...
Interviewer: So, what is your favorite food?
Rowling: Snape kills Dumbledore.
Interviewer: No, I asked... WHAT!?
By the same token, everybody and their grandmas will know the secrets before or on the thing's launch. We knew that Snape killed Dumbledore shortly after the book was released (if you went onto YTMND on that day, you really couldn't miss it no matter how hard you tried. Some guy actually waited outside a bookstore, people walking out with fresh copies of Book 6, only to yell to the crowd "Snape Killed Dumbledore!")
Similarly, we have a month to go, but we already know every character in Brawl (if not, then almost all), probably every stage, every mode, and a bunch of other stuff that we'll know about from YouTube a week from now.
I'm reminded of a RealLife comic where Greg says he can't wait to see Gandalf in the second LotR movie. Tony says "oh man, Gandalf comes back? You ruined it for me!" Greg reminds him that the book's been out for like 50 years, so it isn't really a spoiler. Mm, but then again, I wonder how many people who watched LotR had never read the books. *raises hand*
Smash Bros. Dojo has now revealed a hidden character, as well as how to unlock that character. Wonder who it could be.