In a few years though, I would not be opposed to them regaining the rights, but only after they've tested/proven the viability of other properties.
I will say this. I think Fox is definitely making a stronger effort with the film properties they've licensed. First Class easily the best of the X-films, though the longer it went on the worse it got (imo). Had it just been Magneto Origins it would have been a stronger film. For all intents and purposes they have a good team working on the new Wolverine film. They're trying to get Josh Trank for Fantastic Four, which could be very interesting.
Sony is another matter though. They stupidly rushed out a (from what I heard) crappy Ghost Rider sequel just to retain the rights, when really the only thing that does is sour people on the property. Meanwhile, the Spider-man sequel has a strong team behind it and actually looks interesting, although I'm still wondering about the first-person webslinging. I think that's going to pull people out of the film. I don't watch Spider-man to be Spider-man. I watch Spider-man to watch Spider-man.
All-in-all, I think the superhero movie subgenre is going to be seeing a boost.