Maybe things have somehow changed over the years, but as far back as I can remember (and was at all involved) there was actually very, very little that was ever recorded in stereo. The vast majority of true "recorded in stereo" titles that I ever knew of were classical offerings. Practically everything else was recorded to a number of tracks (4, 8, 16, etc.) and then post-processed (mixed and produced) to construct the final product. With the notable exceptions of stuff like the Beach Boys (mostly mono) the non-classical stereo releases from about the mid-to-late 60's and on were "stereo constructions". The source material was all pretty much discrete and they were built/mixed from some number of these discrete source tracks - it really was all kind of a trick and often not at all a record of a single coherent performance.
The vast majority of material released over those decades was mixed to stereo and that's what the vast majority of us grew up with and what we acquired our gear for. That's what we're used to (so that must be the best?). Quite a few of the multi-channel releases (SACDs,etc.) aren't any real improvement over the original stereo release - they lack the original's fresh emotional impact and aren't new and compelling ('cause we already heard 'em in stereo). However, if you ever do get a chance to hear offerings like this ABB SACD then y'all might understand Mig007's reaction. There really is a whole lot of older stuff that was just not just all that well done for the original (stereo) release. Some of those (like the Fillmore East, Layla, etc.) really do get more of the mix they deserve in their latest incarnations - and they just happen to be on multi-channel SACDs. If the same care had gone into all those original stereo constructions the differences probably would not have been so striking (and this thread might never have started).
Do you prefer all your movies in stereo? Some only really need a center channel, but some only truly come alive with the multi-channel treatment. I just like mine well-done - stereo or multi, as appropriate.