I am also wondering if the Thorin Azog theme (which is NOT a Knife in the Dark) will be available.

Everyone keeps saying this is a Knife in the Dark, but it is really a Mordor motif heard of course in anything Nazgul related. The version in the Hobbit has staccato strings and heavy timpani that no prior version has. This theme looks to be a sort of remix, or building up of the earlier theme to echo the Mordor connection, which we will probably see in some fashion with Azog and the Necromancer.

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The music was stuck in by Jackson because there was last minute editing being done and he needed something and nothing else could be prepared in time. Remember the decision to make this three movies came quite late in the game. And similar things were done during TTT which was a rush job in many ways.

There were some themes in LOTR that changed 'alliances' or broadened in meaning.

From my website:
History of the Ring theme: HS had originally referred to this music, heard at the Argonoth, as a theme for Gondor Theme . But in the appendices of TTT EE DVD, he refers to it as the 'History of the Ring' Theme and that name has persisted since.

Shore quote from FOTR commentary: There’s a theme that’s used in the very beginning of the film that has to do with the history of the Ring. Cause in the prologue is explaining how the ring was forged and all historical references to the Ring. And there’s a theme that’s used there that’s actually a Gondorian theme that you hear as the Fellowship goes through the Argonath and then into Amon Hen. We see ruined statuary of Gondor and you hear that theme.

This music all has to make sense but, ultimately, it is a active, breathing, creative art form. It is not math with Venn diagrams and spread sheets. I think the fans have pushed for the theme concept to be much more concrete than Shore might have liked. If we weren't all studying it so intently, would we notice the use of the Ringwraiths, Martial Lothlorien, or Gondor Reborn themes as being 'out of place?'

I guess, ultimately, it remains to be seen as we either get an explanation that illuminates it all or we get a 'don't be too literal' explanation.

Well, not really an answer, but just an idea of where this charge down the tree music comes from. It is not based on A Knife in the Dark necessarily, but much more based off of the music from the prologue in FOTR. If you go back and listen here:

@2:15 http://www.youtube.com/watch?v=GNx8tz4qVeI

you can hear the theme all the theme play out including the dramatic drums that are similar to those when Thorin is clinched in the jaws of the Warg and then thrown. However, it has definitely been re-recorded for The Hobbit and scored originally to match this film. It is clearly not a Ringwraith only theme, but a Mordor theme or even something else that I'm not sure I should say. I'll say it, but I must elaborate:

If you think about the Ringwraiths and Sauron and the enemy in general, what are they? They are prideful, twisted, vengeful, full of malice, and anger right? Well, Thorin is not a bright, righteous, and noble character per-say. He is very deep and complicated. Now, what is Thorin doing in this scene? He is filled with pride, anger, vengeance, and dare I say malice himself. Instead of doing the noble heroic deed of turning to save his fellow dwarves from falling to their deaths, he rises and charges alone, foolishly and pridefully. Pride comes before the fall and fall Thorin does. I feel the music, while it was jarring for me at first too, is unbelievably genius on the part of Jackson and Shore. Had the finished film stuck with the original scoring, if it was even the original scoring (it seems to be the case), thorin would have looked as if he was making the heroic and noble decision. The music would have told the wrong story. With this finished product and, for lack of better term, "Nazgul theme" we cannot help but see Thorin's weaknesses being revealed to their full extent, by his foolish and prideful decision.

So to sum it all up, the theme may not be Ringwraith or even Mordor, but now it seems that the theme is really about ill intent, malice, anger, vengeance, pride, and so on. Thorin's companions are dangling over the cliff, about to fall to their death and yet he chooses to go on a suicide charge alone. It is foolish, so therefore he gets this dark and dramatic theme for his dark and prideful charge.

This is a fantastic discussion and I loved reading all the previous posts! I hope my post helps and if it doesn't I'm sorry. This is all just my opinion of course, but I for one loved the theme that was used. I don't feel it can really be labeled the "Nazgul theme" fairly since it was used heavily in the prologue and no Nazguls were present. Now it is also used for Thorin. So, take my thoughts as you will.

The goal is multifold, imo. First, to seek to be educated about as much as one can, from as valid a source as one can. Second, to allow for thoughts other than the 'official line' to exist and be discussed. Third, to understand the difference between the two approaches when forming an opinion, stating a point, or debating an issue. That goes for both 'sides'... that is: people who gravitate towards one approach strongly. If you're all fact based... lighten up sometimes. If you're all personal opinion based... educate yourself. Learn to listen as much as you like to talk. Understand where the other party is coming from and allow for differences in approach.