I've known this for awhile. He's also in the new Riddick movie. This will launch him up really high. It depends on how well this does. It's kinda nifty since nobody knows GotG but people know Iron Man and others. So it's going to be really hard to determine how this plays out.
Guardians of the Galaxy is also gonna get a sequel if this does well. Plus Thanos is the villain for Avengers 3 so GotG has an even more reason to appear.