That would make zero sense since 20th Century Fox was a Blu Ray supporter. What makes you think Lucas would choose a already backwards and obsolete technology when he could support Blu which had more drm to protect his movies.
I believe That the Clone Wars movie may well be the first star wars title on Blu Ray. We already know the first Lucasfilm title on Blu is going to be Indiana Jones IV. But i would just a soon spend my money on The Dark Knight Blu Ray if i was a blu ray person.