Filmonic has discovered that WB has revealed the composer for Harry Potter and the Deathly Hallows: Part II!  If you go to the About the Movie page, then Filmmakers and finally under Alexandre Desplat’s information page it says:

“He next starts work on ‘Harry Potter and the Deathly Hallows – Part 2,’ the conclusion of the Harry Potter franchise.“

So there you have it, Alexandre Desplat and not John Williams (as was previously thought and rumored) will be the composer for both parts of Deathly Hallows.

Thanks Mugglenet!