This situation began a few weeks when it was announced that the Marvel vs. Capcom games were being removed from sale on PSN and XBLA. Now another Marvel licensed title has been taken down from PSN, XBLA and Steam, that being Deadpool.
If you search Deadpool on Steam you only get links to a trailer or Lego Marvel Super Heroes, while on PSN you just get costumes for the LittleBigPlanet games, and on XBLA an error message is displayed. It’s quite a big removal considering the game only released six months ago in June.
The removal of Deadpool shows that something is going on with the Marvel licenses. My guess is that Disney are taking back Marvel properties to develop games themselves instead of striking deals with third party publishers such as Activision or Capcom.
Or Disney has been unhappy with how the properties have been used by these publishers so will be moving them somewhere else like EA, who have the Star Wars license, or Ubisoft. Considering how big Marvel heroes are at the moment, Disney will want to have games that are met with positive reception and profit.
UPDATE: It has been confirmed that Marvel and Activision have terminated their licensing deal and the following games are no longer available:
Spider-Man: Friend or Foe, Spider-Man: Web of Shadows, Spider-Man: Shattered Dimensions, Spider-Man: Edge of Time, X-Men: The Official Game, X-Men Destiny, Deadpool and X-Men Origins: Wolverine