Michael T. Coleman voices Cody, giving him a neutral-sounding accent, dipping occasionally into a more Brooklyn-sounding accent, as evidenced with his intro and some of his attacks (i.e. "Criminal Uppa!").
Todd Haberkorn and Johnny Yong Bosch voices Yun and Yang in english. For their cameo in Chun-Li's prologue in the non-AE games, Ted Sroka (the voice of Dan in english) voiced both of them.
Anthony Lander (Golbez) voices Zangief in english.
Shrug of God: The Arcade Edition and the game's staff are insisting in every way possible the ambiguity of Oni's identity, he who basically all fandom has accepted as a new Super Mode for Akuma, but the in game material still says otherwise: the character is just named Oni, all of his available quotes so far bares almost no connection to Akuma aside from their power-hungry nature, his fighting stance resembles Gouken's more than anyone else, his face has minor differences compared to Akuma's (notably the nose), and the already leaked ending is even more dull than Akuma's as one cannot tell anything about the character by just watching it (well, except the fact he can destroy volcanos with a single punch and possess flight abilities); still it is safe to say that the logical conclusion is that Oni indeed is Akuma. Word Of God finally confirmed Oni as Akuma via Seth Killian.
Originally, Rufus was named "Cobra King," and was a lean muscular black man wearing a stylish karate gi◊. He was still planned to be acrobatic fighter, but employed a fusion of breakdancing and kung-fu (breakung-fu) instead of his self-taught kung-fu. Marketing research on the preferences of American gamers had a big hand in Cobra King's design.
Then, SF4's art director suggested that Cobra King should be made overweight. The series of changes after that led to Cobra King becoming Rufus. According to SF4's producer, they used Rufus' current look because it would "freak people out," and because "over-the-top" characters sets Street Fighter apart from the other fighting game franchises.
The gi would later be used as an alternate outfit for Ken.
T. Hawk and Dee Jay were originally going to be in vanilla IV. Both of them joined the roster with the release of Super.
R. Mika, Karin, and Elena were considered for Super. Series Producer Yoshinori Ono said that if DLC characters are released, R. Mika will be among the first. In fact, Elena barely missed the final roster for Super Street Fighter IV.
Ono also mentioned that he wanted Final Fight's Rolento in the mix as well.
Concept art shows that Guy's alternate outfit in IV was planned to be Strider Hiryu.