Street Fighter X Tekken news has been pouring in steadily since Comic-Con last week and the majority of it has been new character reveals. Between the two franchises bumping heads in this titles, there's no way that every character from either universe couldmake the cut. The roster would quickly cross one hundred unique characters. So, a savvy interviewer asked Yoshinori Ono about a couple of characters that wouldn't show their faces in the upcoming crossover. The two characters are Anna from the Tekken series and Dan from the Street Fighter series.
Dan will not be included because he was apparently killed in an SF X T trailer shown at Comic-Con last year. Anna will not be included specifically because of Nina's inclusion. I can totally understand Anna's omission. In a game where you want to get as many different play styles as possible in, with characters from both sides, Nina and Anna are simply too similar in some ways. This isn't to say Anna wouldn't have been a fine inclusion. Dan's omission is actually a tiny bit more shocking because he seems like such a mascot character for the SF series. His game-play has absolutely never been anything special though, so I don't see it hurting the overall roster.
Ono also dropped a hint at the inclusion of Paul Phoenix from the Tekken series, after noting that Paul and Nina were his favorite Tekken characters and saying that he hadn't announced Paul "yet". I think Paul's inclusion is a given considering he's a series staple like Nina, Kazuya and Yoshimitsu, all of which have already been confirmed. Street Fighter X Tekken will be available on HD consoles in the first quarter of next year.