What's interesting about the characters mentioned (Dhalsim, Yoshimitsu, Poison, Steve Fox, as well Cole) isn't the ones that you would expect for a game titled Street Fighter X Tekken, but the additional characters. Poison, being a character from Final Fight (another of Capcom's properties) seems to set a precedent in the game to try and transform it closer to the existing Marvel vs Capcom series which saw the release of its third game earlier this year. Then, as a bonus character, Cole from Infamous is offered to Vita players of which feels like an attempt to grab Playstation players that would otherwise not play this fighting game.
As more characters are added that are not from the ranks of the titular games, it has me questioning the level of success that will be achieved. There very well could be a backlash from including these characters in either sales or the community in general. People are quite apt to follow a divide that has been set in competitive games by the community in order to attain a level of respect for playing the game. Personally, I hope that it won't impact either the sales or the community so that we can see even more cross-over games perhaps extending outside of the fighting games genre.