As reported by GoNintendo this morning, Official Nintendo Magazine (UK publication) had the following quote in their Brawl article, in relation to a yet unrevealed character, signified with a question mark:
“Your guess is as good as ours, although we’ll point the finger at Krystal, Fox McCloud’s princess friend; £5 says we’re right.”
This is not a confirmation, of course, but it is interesting that even an officially licenced publication thinks that Krystal will be the next revealed character. Hype about Krystal, deserved or not, is good!
Update
An image of the page has been posted at the Smash Boards.

Your comment on GoNintendo was put together very well Mr. Krystal.
I’m just astonished by the random characters that people want in Brawl…and the hating! THE MASSIVE AMOUNT OF HATING! I don’t understand the hatred towards Krystal, and no matter how much people will try to explain it to me (leaning towards one way or the other), I never will.
Speaking of hating, a fellow British mag ‘NGC Magazine’ (Now ‘NGamer’) seems to have it in for Krystal, citing her as a “reject from Dinosaur Planet”. I’ve cancelled my subscription. :p
I’m starting to wonder if they’ve simply stopped announcing characters. It seems likely that Krystal would be next on the list, but I wonder if they cut it off right where she would come on. How disappointing would that be?
@S. Weltzin
Very disappointing! :(