Sky will continue with the PayTV rights for Bond but it does not make sense financially for MGM to sell the rights exclusively to one provider when they can make more money selling them individually. I have no doubt that ITV will show Skyfall once they get the rights back.
Think Bond is one of the few franchises which are sold separately from other film output deals, Star Wars, Potter and Indiana Jones are the others. I wonder if Disney will sell Marvel and the upcoming Star Wars films separate from their other films or bundle them together.
I would imagine Star Wars and Indiana Jones are only separate because Lucasfilm owns them outright, rather than them being studio owned (before the Disney acquisition of course)