KARADIN

Thor will no longer be able to wield Mjolnir, a woman will now take up the hammer, and will be called Thor. (refreshingly not Thora or She-Thor or Thorina. (Though the new Thor might simply be the character Angela)

Sam Wilson (the Falcon) will become Captain America when Cap gives up the shield (not for the first time) incidentally, this is not the first Black Cap, that honor goes to a recent storyline where a black solider Isiah Bradley was given the serum in WW2 with references to the Tuskegee Experiments, his grandson is now Patriot who fights with the Young Avengers.

Iron Man will also be getting a reboot as Superior Iron Man, who is an anti-hero. Not sure why that's Superior.

But eventually, beside the stunt casting, you'll see original Tony, Steve and Thor come back, which makes a few reviewers (and myself) wonder if it would be better to simply create new characters in the Marvel universe that are diverse, rather than have these limited series. (yeah, new FalconCap is gonna have Rick Remender as a writer still, BLECH offensive-no-one-cares storyline that tanked Captain America sales)