Doctor M said:
While reviews of the current BD are good, the aspect ratio is NOT theatrical, measuring 2.24:1 instead of 2.39:1. Dunno why.
It seems to be due to laziness. The 2k master is 2048x858 (2.39) and instead of doing a proper rescale, they've cropped the edges off to make it 1920x858 (2.24).
*headdesk*
Edit: Just tried the iTunes download and it's in the wrong aspect too.