The "first major Marvel Comics event of 2014" gave up a few details earlier today in a live chat. Here are the highlights:
-Original Sin is eight issues, written by Jason Aaron with art by Mike Deodato. It begins with the body of the Watcher being found on the moon.
Aaron: "It all started with the idea of a murdered Watcher, which would put all of his most treasured secrets up for grabs. Once I grabbed hold of the story, it was up to me to figure out who killed him and why."
-Tone will be an interesting mix of gritty murder mystery and epic cosmic stuff, "Like mixing Kirby and Steranko and Grant Morrison with some Garth Ennis."
-Nick Fury is the lead investigator. Thor and Cap will be heavily featured. Dr. Strange, Black Panther, Emma Frost, Punisher, Moon Knight will also feature strongly. Punisher will team with Dr. Strange and go into other dimensions. Emma will team with Ant-Man (Scott Lang). The villains are being kept a secret for now - Aaron says we'll never guess.
-It won't delve more into the origins of the Watchers - just give new readers all they need to know before he dies.
-Gamora from Guardians of the Galaxy is a significant player. She'll team with Moon Knight and Winter Soldier.
-Uatu is not the only casualty.
-All of the characters involved were chosen for "very specific reasons."