I find this rumor hard to believe but nevertheless it's an interesting one...
The rumor comes from TheDailySuperhero and is the same source who first revealed Marvel's interest in Bradly Cooper (now playing Rocket Raccoon in Guardians of the Galaxy):
According to one of The Daily SuperHero's insiders in Tinseltown, a rumor is circling through several inner circles stating that the buzz surrounding the Cumberbatch rumor of being in Star Wars Episode VII might be something that has been manufactured by Disney. This distraction is being done to help conceal what Disney really wants the actor for... and that's to be in a future Marvel Studios film.
The contact was once again vague in saying what Marvel Studios role Cumberbatch might be targeted for but there is definitely a tremendous amount of interest by the studio. If this is indeed true, it sounds like a very tricky maneuver by Disney and this is not out of the ordinary since it has been rumored that Disney and Marvel like to leak false info to throw off the media and misdirect fans.
Although I really like Benedict I still believe that Abrams won't use any members from the Star Trek cast.