i don't think a box set is coming anytime soon considering lucas is still tinkering with his prequel films, and 2007 will see episode one in 3-d with the all digital yoda. 2008 attack of the clones, 2009 revenge of the sith. with lucas one a year policy that means his super duper special editions 3-d version of the older trilogy will be 2010 a new hope, 2011 empire strikes back, and 2012 return of the jedi.

he still has yet to decide on the new format war but I bet because of 20th century fox it will be blu-ray

and also because he had been the main force behind pioneering the digital film revolution and dlp technology.

i'm pretty sure they'll still be a dvd six box set though, if not it will be skipped and jump to the blu ray player, but since he likes to go to the well as many times as people will buy them, i think he will squeeze all the cash he can out of us. My advice is you already own them don't bother buying them again unless he releases the oot in anamorphic widescreen with 5.1 and digital restoration, and all the old documentaries and deleted scenes.