Just a few comments on this sequence:
The stair? It looks like a cliff to me, with some scratches in it to suggest a stair - and while I realise that is more dramatic, if they are going to scale cliffs, why not do it somewhere other than the Witch-King's back yard? Yes, I realize it's essential to the plot, but they could have thought about the logical implications of making the stair nearly unclimbable (except to Sir Smeagol Hillary, of course.)
Regarding Minas Morgul: I never liked the neon green=undead equation, here or elsewhere. It doesn't seem quite as far off here as it does in the upcoming paths of the dead scene, but still, it bugs me. To me, neon green says "hippie" or "early 80's", rather than "undead monsters", but maybe I'm the only one who feels that way. *shrug*
There is one orc among those attacing Osgiliath who quite obviously throws both arms above his head and runs into a sword. "Geronimo!" - it's actually pretty comical.
Oh, by the way, I realise everybody's sick of hearing me mention this guy, but that wasn't Lawrence Mackore calling the fell beasts nazgul ... it was Andy Serkis.. You see, his voice was the "added demonic force" given to the Witch King that allows him to break Gandalf's staff
(sticking my tongue out at PJ, not you!)