The amazing destroyer of sleep known as TVTropes.org has an entry it calls Fridge Brilliance. This is the moment when, some time after you’ve experienced a piece of entertainment, things suddenly click in your mind and something that didn’t make sense about it before suddenly does.
A personal example comes from the choice of the Chitari as the alien stormtroopers in Avengers. Whedon and Disney used these aliens that originated in the Ultimate Marvel universe not because they have a cooler name than the Skrulls, or the Kree, or the Shi’ar, but because that’s what was available. The Skrulls are mostly a Fantastic Four enemy, and the Kree first appeared in that title as well. Just like the Silver Surfer, Fox probably got those races. They’re also probably sitting on the Shi’ar, who generally appear as adversaries or allies to the X-Men (depending on the day of week and how nostalgic the current writer is for Chris Claremont).
Those are the Big Three alien races in the Marvel Universe, the ones that would get fanboys most excited, and Disney can’t use them yet.
But the Chitari? Yeah, they first popped up in The Ultimates, which is the Ultimate Marvel version of the Avengers.
What I don’t quite get, then, is how the War Machine armor is able to look like this in Iron Man 3:
That’s the Iron Patriot armor, originally worn by Norman Osborn when he was given temporarily given control of the Avengers.
Norman Osborn is better known as the Green Goblin.
The Spider-Man villain.
Whose rights are held pretty tightly by Sony.
Now, as I understand it, the story goes that Osborn just took an old Iron Man armor that became his property when he was handed control of all the super-heroes and repainted it to suit his needs. Maybe that’s how the Disney lawyers managed to spin it.
And now Whedon’s hinting at Quicksilver and the Scarlet Witch in Avengers 2. Mutants both, who first appeared in the X-Men as members of Magneto’s Brotherhood of Evil Mutants before Stan Lee decided he liked them enough to make them good guys and Avengers.
That’s what happens in a shared universe. And it’s not just an issue that can crop up in comics.