Warner Bros. screened raw footage from Harry Potter and the Deathly Hallows at ShoWest.

The clip was introduced by Alan Horn and you can check out two reports below1

Cinemablend:

The footage shown came from all sections of The Deathly Hallows, so it's impossible to tell where they will split up the two movies. We saw little bits of everything, from the seven Harry Potters escaping from the Dursleys house (totally surreal) to the attack at Bill and Fleur's wedding to the escape from Gringotts on the pale dragon and even Hogwarts on fire. With unfinished effects it's hard to really say how it all looks, though some of the most effective moments were the simplest-- Ron and Harry's fight in the tent, Harry visiting his parents' graves, running away from the Snatchers in the woods, Harry defiantly telling Voldemort that he stays alive "because I have something worth fighting for."

One odd moment-- one of the final shots was of Hermione riding a broom, by herself, escaping from a fireball that's likely the curse that Crabbe and Goyle set off in the Room of Requirement near the end. Did Hermione ever ride a broom by herself in the books? Is this a change that will mean something bigger, or just something convenient so the movie doesn't have to bother explaining that Hermione isn't good on a broom?

Collider:

The footage started with Voldemort walking in the forest with all of his followers around him. He was looking for Harry. While I assumed the footage was going to be just from the first Harry Potter movie coming this November, I think the opening was from part 2 and it was from the big climatic battle between Harry and Voldemort!