My wife and I watched Die Hard 4 last night and I would have to say this was the BEST sounding movie I have heard in my theater. We listened to the DTS core of course (I can't wait until the PS3 can play the full DTS-MA) so I wonder how much better the actual DTS-MA is. Anyway, from the sound of the guns (bass), explosions (bass) miscellaneous sounds (surrounds) and clear dialogue I would rate this as the best sounding Blu-ray out there.
One thing about the movie is the surrounds get used A LOT. I would say probably 65-75% of the movie takes advantage of the surrounds. I have a 7.1 setup and all 4 of my surrounds were active for most of the movie.
I have Blackhawk Down (as well as a few of the other tier 0 ranked movies) and have heared its pcm track, but I believe Die Hard 4 should be rated as the best Blu-ray for audio, at least as far as I have heard so far.
I haven't seen War or Shoot em Up, I have heard good things about their audio as well, but as of now Die Hard 4, to me, is the best sounding Blu-ray available.
Rotel RB 985 amp
Monitor audio silver series speakers
Axiom Qs8 surrounds (7.1 system total)
Dual HSU HO and MBM