I agree that the above leak of Magneto, Polaris, Cyclops, and Apocolips sounds fake. Especially Polairs. Then again we have to remember that it's not necessarily what Capcom wants in and what characters they think would be good, but what Marvel let's them put in. Like the hint that Cyclops might not be in when asked if there was anyone Marvel didn't want in. Cyclops seems to get the short end of the stick a lot even if he is a good character fans of the MVC series would want in. Maybe Capcom asked for Cyclops and Phoenix, and Marvel said no, put in Polaris instead of Jean.
I mean I don't believe the above 4 were leaked. I guess I'm just more willing to be open to someone being put in or left out the more I hear that it's really up to Marvel on who they allow. For all we know Spiderman may not have been announced because rights to put him in games have been given to someone else (not saying that's true, was just an example).
As for Megaman and Zero, I'd like both. They play differently enough that they could both warrant a spot. I've wanted to see Zero in a MvC anyway, and Mega pretty much needs to be in it. Also as for which Mega, I'd like for it to be Megaman X so he could use his special armors from the X series as supers. You could always add the other Megaman's as alternate skins.