The bad news, at least for Star Wars and film purists, is versions of A New Hope, The Empire Strikes Back and Return of the Jedi in the set will be the modified special edition versions (re: Greedo shoots first) and not the original versions. Lucas explains the reasoning behind this decision to the New York Times.
"You have to go through and do a whole restoration on it, and you have to do that digitally," he said. "It's a very, very expensive process to do it. So when we did the transfer to digital, we only transferred really the upgraded version.... [it's] kind of an oxymoron because the quality of the original is not very good."
I'm not convinced Lucas is being entirely forthcoming about his plans with this statement. There are only a few minutes of film that differ between the original and special edition release that would need to be cleaned up and transferred for Blu-ray. It sounds more like Lucas is putting additional dollars into supplemental materials now and will revisit the "original" trilogy a few years down the road - say 2015 or so - to re-energize the franchise/brand after making loads of cash off the first Blu-ray set.
Given Lucas' track record with multiple versions of Star Wars on VHS and DVD you have to imagine the door for the unaltered films on Blu-ray will never truly close.
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