^Annihilation was in 2006.
And it didn't (directly) affect earth.
Also, I love how all of Marvel's events lead into another rather logically instead of being a huge clusterfuck like DC's "Crisis" crap.
To be fair, Bendis and Quesada have been planning this for years.
My understanding is that coming out of this there will be a new Avengers team in a title called Dark Avengers. Mighty and New Avengers will continue, however, along with Avengers: The Initiative. Captain America (Bucky) may become a New Avenger also. Iron Man's solo title will be retitled "Iron Man: World's Most Wanted".
Ms. Marvel's prominence as a character will be increased. The current events in her solo title which show her before she became Ms. Marvel are somehow linked to Osborn. Uncanny X-Men Annual #2 is listed in the Dark Reign tie-ins and as such I would guess it's going to focus on Emma Frost.
The events in the recent Namor mini-series make more sense (Atlantis being destroyed and its people becoming sleepers throughout the world), now. Also in Thor, there were early signs that Loki and Doom were working together.