Since there's been some interest I'll post this. At the San Diego Comic Con a preview of the EE was shown, and here's some of the stuff we can expect in the 50 minutes of additional footage. I didn't write this by the way:

Warning: Pretty Thorough Spoiler

-Frodo and Sam at Cross Roads
-Mouth of Sauron w/ Mihril Coat
-Gandalf vs. the Witch King (WOW) The Witch King's blade catches fire.
-Saruman of course. He was on top of Orthanc. He gives a speal and says 'You are all going to die.' He also slaps Grima. He shoots a firebolt at Gandalf.
-More Faramir and Denethor dialogue. More Boromir flashbacks?
-Faramir/ Pippin talk
-Faramir and Eowyn at Houses of Healing
-White tree shots
-Major scene in Paths of the Dead. Thousands of skulls pour from the walls.
-Aragorn and Co. see Corsair ships
-King of the Dead charging
-Eowyn fighting Gothmog
-Brutal Mumak trampling
-More Nazgul swooping
-Sam and Frodo in orc regiment
-Sam and Frodo on Mt. Doom looking to sky
-Cirith Ungol shots
-Lots more siege of Gondor orc fighting
-Eomer finding Eowyn
-Eowyn in a robe lying down in Edoras, grabs Aragorn's hand
-Merry bowing to Theoden
-Eomer and Aragorn in Rohirrim Camp
-Gandalf and Pippin in Minas Tirith
-Aragorn goes into Gondor throne room along, looks into Palantir. Shows Sauron Anduril.
-Another battering ram on Gondor gate
-Billy Boyd told us about a scene. After Pelennor Fields everyone goes back to Gondor..but Merry is still missing. Pippin looks all day, never giving up. He finds Merry (scene in theatrical, except its night).