I really hope Bob's wrong about Marvel maybe introducing Marvel/Miracleman in Age of Ultron. See, Marveleman was really only notable for Alan Moore's reworking of him, before that he was just a generic,ripoff of Captain Marvel and by extension Superman. The Eclipse Comics stuff though, put him down into a world where there were no other superheroes and Moore wasn't bound by a status quo, which allowed Moore to go crazy with the character, throwing him into apocalyptic battles and dark conspiracies and questions about identity, ultimately ending the series as a quasi-benevolent dictator of a transformed Earth.
Putting Marvelman into the the Marvel universe though, would mean that he can't do any of that stuff, because at the end of the day Marvel Comics wants their fictional universe intact so that they can still tell stories and sell comics with the X-Men and Thor and all their other properties.
We saw the same thing when Marvel introduced the Sentry, that kind of superman-analogue just doesn't fit into the Marvel Universe's paradigm, so they're left awkwardly shuffling from story to story, no writer ever quite sure what to do with them.