If Sonic is in the game, I think it will be advertised. The OMFG moment will come in about the 3rd week of November right before they start running ads, when he is revealed on the website.
"[Our former customers] are unable to find software which they WANT to play."
"The way to solve this problem lies in how to communicate what kind of games [they CAN play]."
Satoru Iwata, Nintendo President. Only slightly paraphrased.