From scifi.com (spoilers):
USA Today got a preview of the upcoming extended version of The Lord of the Rings: The Two Towers and offered spoilers about the DVD's added scenes. The three-hour, 43-minute extended cut reaches shelves in a four-DVD collection on Nov. 18, timed to the Dec. 17 theatrical release of the third Rings movie, The Return of the King, the newspaper reported.
A list of some added scenes, according to the newspaper's spoilers, follows.
•Sean Bean's Boromir, who died at the end of 2001's The Fellowship of the Ring, is resurrected in a lengthy DVD flashback after brother Faramir (David Wenham) finds a boat bearing his body.
•The twisted emotional ties that ensnare ruler Denethor (New Zealand actor John Noble, who officially joins the cast in King), his favorite son, Boromir, and scapegoat Faramir also are exposed. The scenes also help explain why the noble Faramir is rude when he meets Frodo (Elijah Wood) and Sam (Sean Astin).
•Rohan horseman Eomer (Karl Urban) finds his mortally wounded cousin Theodred and brings him home, where his subsequent death goes all but unnoticed by his father, King Theoden (Bernard Hill).
•The plight of Eowyn (Miranda Otto), Eomer's sister, deepens as she sings a mournful dirge during Theodred's funeral.
•The truncated encounter between Treebeard the Ent and hobbits Pippin (Billy Boyd) and Merry (Dominic Monaghan) is expanded.