A lot of people are speculating about who's gonna end up taking Norman out of power. Some think it'll be old rival Spidey, others think it'll be Iron Man getting revenge or Captain America coming to the rescue again. His "partners" seem like likely candidates too, since they all seem to hate him, judging by his portrayl in Thunderbolts and Dark Avengers. Or he might just end up screwing himself over- it wouldn't be the first time he ruined his career and his reputation just to get his kicks for a few hours flying around on a Goblin glider and blowing people up.
Quite frankly, though, I think the best way for Dark Reign to end would be for Norman to get his comeuppance from his oldest victim: The "Robot Master," Mendel Wardell Stromm. I recently heard that they brought Stromm back in the Penance one-shot, and I wouldn't expect them to bring up such an obscure and forgotten character unless they were planning to use him more in the future. And it would be the one ending practically no one would see coming.
If it's Iron Man, then it'll probably be a battle of both fists and words where Norman reminds Tony about how he used him to shoot that Alantean official and that 42 and the cape killers were nothing more then quick fixes from a man who was panicking and thought being a brilliant inventor made him have all the answers while always making the problems worse. He also mentions that this Dark Reign was his creation and all Norman did was take over.
Tony then admits that Norman is right and that Captain America no doubt knew this would happen because he was always more down to earth then him and in the past he always tried to prevent him from going too far because of his arrogance.