I found this on that site it looks like black cat won't be in it. This screenwriter note is important to state at this point, because most of what is online about the new characters in this sequel comes from actress Kirsten Dunst, and it all predates the Koepp news in early June. In other words... if Koepp is doing his own thing separate from what Millar and Gough started on, it's possible that anything Dunst said before June 11th, 2002 is no longer true. Koepp's story idea may have completely different villains (at one point, the villains of the first film were supposed to be the Sandman and Elektro, for example).
Specifically, Dunst first told ComingSoon.net back in April, 2002 that the villains were to be Doctor Octopus and the Lizard. Dunst then told "Wizard" magazine in early June that Felicia Hardy, aka the Black Cat, may be brought in as a romantic interest for Peter in this second film (this was also before Koepp came aboard). Since both of her revelations predate Koepp's new story idea, however... they may both be completely irrelevant at this point. I do have a hunch, though, that even if the Lizard and the Black Cat are dropped, Doctor Octopus probably does remain a shoo-in to be one of the villains in this movie.