Whatever version of SW/OT came out in 2004, whether it was the OOT, '97, or the '04 version, they would have sold pretty much the same numbers. Sure if the OOT were released that year, the numbers would have been alittle better, but the masses will not nitpick when it comes to which version they want.
For example, I like ET, but it is not one of my favorite movies of all-time. When it was first announced in 2002 for DVD, it was only going to be the SE, and I was sorta mad, but I still would have bought it. In the end, the Original Version was added last minute, mostly cause it didn't well in the theater, and they added that version when the DVD came out in October, but the bottom line was I was buying it cause it wasnt life or death to me, although I preferred the Original ET version.
Same goes with the OT, 95% of the fans prefer the OOT, but most fans aren't going to go crazy if Lucas puts out the SE, and like myself with ET, they will settle for whatever comes out. Lucas has one shot to get the masses for BluRay, just like he had for DVD, and just like he had on Laserdisk. After that, he then has to tweak each edition to get the diehards to buy it again: Deleted Scenes? OOT remastered? PT with added scenes? New documentaries?
So OOT could be on the horizon when SW BluRay hits the shelves, but if it is the SE, then it will do just fine sales-wise. And that makes me sad, but there isn't much we can do about it.