I would say this will happen sometime within the next ten years but no one can really say when--maybe next year or the year after if it comes out on HD disk or the infamous "Saga" boxset on DVD, maybe in five years when they do a big deluxe HD boxset, maybe it will be a whole ten years before the cries of "where is Star Wars?" overwhelmes all other Lucasfilm operations.
The whole thing comes down to Lucas really, and the threshold of "last video release" has already been broken with the 2006 re-issue, so Lucas' philosophy of "SE only" has been nullified, which means it will, at some point, be out again. I think the reason that Lucas said in 1995 that it would be the last release is because he was certain that no one honestly would want the older version, and I think a lot of fans thought they wouldn't want it either. Flash forward to 1997 and the SE is not just a new Jabba scene and more sophisticated FX, and people realised there was still a big place for the original version, especially since the SE had so many changes. Lucas, caught off guard by the negative reactions, says "but this is the version I want people to see, its better". Then the prequels come out, Lucas gets crucified, fans are saying he's a hack and the OT is better and the SE sucks and they only want the original versions--then Lucas says "like hell you will." I think he was just reacting to all the flack he got. This whole issue became especially important a few years later when he made the second special edition with prequel tie-ins--the OOT was now a part of a different series in some sense, and with him genuinely wanting audiences to accept his new PT-based series of "The Tragedy of Darth Vader" he didn't want to give people the option of rejecting this, especially since he honestly believed that this was an artistically superior entity. And thats why he says at this time "this is the only version I want people to see"--it was the only version compatible with his new series, based on the PT storyline.
But then things kind of die down a bit, the prequel flak started to dry up and Lucas might have gotten a bit of objectivity, and with the 30th anniversary coming up Star Wars became increasingly viewed as not some rougher version of the 2004 release but as a real cinema classic that conspiciously was unable to be viewed by students, scholars, fans or just plain viewers curious or preferring this. The whole multi-version home video craze started at this time as well--2 versions of every Alien film, 3 versions of Dawn of the Dead, 2 versions of Apocalypse Now, three versions of Close Encounters and both versions of ET. Lucas' friends all sucked it up and put out the earlier versions of their movies, and I think this might have given Lucas some perspective. Add to this--fans were bootlegging their own LD transfers. The film was out there whether Lucas liked it or not. So when Jim Ward asked Lucas yet again to put out the OOT he said, "fine but I don't want to spend all the money to restore it."
Bootlegs I think were the primary reason why it was put out at all, but if it was just that I don't think he would have done it if he hated this version as much as people surmise he does--after all, The Holiday Special has been bootlegged since the 80's, and we don't have that being released. I think Lucas realised how silly he was being. And if you listen to Lucas interviews from this time period on why he only allowed the pre-existing video master to be used and not a new one created--he says because he believes that it would cost millions of dollars to restore and reconstruct the OOT. He's weakened to the point where he is willing to acknowledge the film for a release but he can't yet bring himself to commit so many funds to it, perhaps simply because he believes there isn't enough audiences to justify it. But he's simply mis-informed--it doesn't cost millions of dollars, simply scanning a release print, an IP or better yet that wonderful Technicolor print that was used as the basis for the SE restoration, doing anything like that would give us a high-res HD image, even if it still grainy like the GOUT (but modern mastering technology would yield a much cleaner image).
So here I think its inevitable that a new transfer is made for HD or a DVD release, and maybe that Lucas will come around to actually restoring it or going back to the O-neg and spending more substantial funds. If not he himself, once he is gone I am sure this will be the first priority of LFL, since it already has been while Lucas is still alive.