Unless Jackson reworked these scenes, The One Ring links describing the EE scenes There are some discrepencies between book and film:
Spoiler:
One from what I have heard of Saruman's demise, it is brought upon himself when Wormtongue throws the Palantir to the company. This enfuriates Saruman, a tussel occurs between Wormtongue and him resulting in the death of Saruman. Entertaiment Weekly published some pics of this scene as we see Saruman impaled on a large spiked wheel.
The scene where Gandalf and the Witchking meet, in the book he basically enters Minas Tirith in after the destruction of the main gate and informs Gandalf that he is helplessly outnumbered.
"You cannot enter here," said Gandalf, and the huge shadow halted. "Go back to the abyss prepared for you! Go back! Fall into the nothingness that awaits you and your Master. Go!"
The Black Rider flung back his hood, and behold! he had a kingly crown; and yet upon no head visible was it set. The red fires shone between it and the mantled shoulders vast and dark. From a mouth unseen there came a deadly laughter.
"Old fool!" he said. "Old fool! This is my hour. Do you not know Death when you see it? Die now and curse in vain!" And with that he lifted high his sword and flames ran down the blade.
Gandalf did not move. And in that very moment, away behind in some courtyard of the City, a cock crowed. Shrill and clear he crowed, recking nothing of wizardry and war, welcoming only the morning that in the sky far above the shadows of death was coming with the dawn.
And as if in answer there came from far away another note. Horns, horns, horns. In dark Mindolluin's sides they dimly echoed. Great horns of the North wildly blowing. Rohan had come at last.
It's a powerful scene and the way it sounds like Jackson filmed it he beefed the action aspect of it, and ruined a perfectily good confrontation scene to begin with. Jackson also ruined IMO the whole Witchking - Eowyn fight by subtracting some great memorable lines from the book and adding action where I felt it was unnescesary.
oh well, I am being nitpicky but I am still looking forward to the Extended cut of the film.