C. Viper In Marvel Vs. Capcom 3
The roster for Marvel vs. Capcom will keep expanding leading up to its release, but it looks like we can cross one more name off the list of probable fighters: Street Fighter IV's C. Viper.
A user at EventHubs noticed a strange new silhouette on a piece of official promo art for the game, coming to the conclusion that Viper is the most likely candidate. After seeing the image (posted below), it's difficult not to agree. That's either C. Viper, or some other Capcom character with a bizarre beehive/pompadour haircut.
Take a look at the image and judge for yourself: