If it became Marvel's "Arkham" series that would be huge for Sony. and it might be a deal like letting them use more characters in return of releasing on other consoles with future games even if its a timed exclusive.
Hard to say. I just don't see why Sony would want to publish on other consoles. They've never done that before.
As for characters to be used - its not based on the movie (as confirmed a few times already), and it seems to be following their own hand crafted path & story, so it could just mean they have full access to the Spidey rogue's gallery (which is pretty damn extensive). Maybe if we're talking Marvel characters outside of the Spidey-verse, but at that point, whose to say Marvel wouldn't just let Sony use them for a Spider-Man game they are solely publishing & funding? Sony having publishing rights on a game like this (full fledged Spider-Man game) means there is just no reason to expect this to be published anywhere else.
Do keep in mind - Disney & Sony have a very, VERY friendly relationship with one another. Its one of the reasons why the MCU deal was done in the first place. Its why Sony will likely be getting marketing deals on Star Wars games from every source it comes (noticed the Lego game during the conference?) from now until Sony either steps out of the game-making business.
Theoretically, if a sequel to this game were to be made & to be multi-plat, then the publishing rights to this series would have to go to another publisher in such a case. Since Disney is no longer in the game's publishing business, and instead are licensing out their IP for games, I just don't know who would pick this up & try & sell the sequel to audiences that won't/can't have access to the original
.
