The Lightening Thief

Immediate Family: Peter Pan, Harry Potter and the Half-Blood Prince
Distant Relative: The Day After Tomorrow

Daybreakers

Immediate Family: 30 Days of Night
Family Gossip: I'm a big fan of the 30DON poster, so when I saw Daybreakers, I was disappointed to see that someone had ripped it off. But then I looked into it: both posters come from the same design house. I'm not sure if that makes it better or worse.

I Can Do Bad All By Myself and Avatar

Ancestor: Straw Dogs
Immediate Family: The Queen, Avatar, He-Man TV show staging
Family Gossip: I Can Do Bad and Final Destination (mentioned here) come from the same design house.

2012

Immediate Family: Graffiti/Revolutionary bills
Distant Relative: 2010
Family Gossip: In the final key art, I think the 2012 font would have been more intriguing in an ancient mayan font. The thin and sleek modern font isn't very ominous.

Saw VI

Family Gossip: The visual read of the Roman "I" could be stronger in this layout. Perhaps if it were not connected to the V shape it would look more intentional.

Youth In Revolt

Distant Relatives: Meatballs, Postcards from the Edge, Stripes
Family Gossip: The use of Cooper black in the key art feels like a throwaway. The Beach Boys' use of it is more committed.

Whiteout

Immediate Family: Fragrance Ads
Distant Relative: Premonition
Family Gossip: Below are some shots of the poster around Los Angeles.

World's Greatest Dad

Immediate Family: Disaster Movie, Epic Movie, most Eddie Murphy movies
Distant Relative: The Great Ziegfeld (very distant!)

Final Destination

Immediate Family: Prom Night
Distant Relative: Straw Dogs
Family Gossip:
The Straw Dogs connection may be thin. But for me, that image is so clever and powerful that any movie poster with broken glass in it owes a debt to the Straw Dogs poster.

The Informant

POSTER #1
Immediate Family: Saul Bass Posters, Dead Men Don't Wear Plaid, What About Bob?

POSTER #2
Immediate Family: Linotype ad, The 40 Year Old Virgin
Family Gossip: A few shots of the one sheet and billboard around town.