Akira Ifukube did the score for many Godzilla films.
To me, the Cloverfield theme? Overture? Sounded like it bit a big chunk off of Ifukube's style, albeit modernized. Though, I guess considering the movei, its to be expected...
And as for the durability of the creature. Why are people complaining that it wasn't hurt? Surely we've established that any good Kaiju style monster should naturally be resistant to the military.