If I'm in one of those multiplexes that shorten the screen right when the trailers start (for scope prints, which is something like 90% of all the movies out there*), then yes, sometimes I do feel inclined to exclaim, "Hey, it's 1.85!" Now, if you mean actually measuring the screen itself and finding out what ratio it's really, actually projected in, that's just silliness on all levels.

*I'm exaggerating. Put the calculators and iMDB down.

There's gonna be another interesting part of this debate when "The Dark Knight" comes out on DVD and what's rumored to be a multi-aspect Blu-ray (I certainly hope it isn't, but it won't look as disastrous as that one film erroneously labeled as multi-aspect, "Dr. Strangelove").

As for the "Godfather" question earlier on this thread, American Cinematographer has an article on the restoration, complete with frame grabs of entire negative frames. http://www.ascmag.com/magazine_dynamic/May2008/PostFocus/page1.php

So it can be confirmed that, like most 35mm productions, the entire frame was exposed. Including the generous amount of headroom on top, and the little strip of dead space on the left to be masked and occupied by the soundtrack. I still wouldn't expect anything other than a 16x9 DVD set.