not that i have a problem with either the fisher jabba scene or portman white jumpsuit scene, but i think the main difference is in the quality of storytelling between the two scenes.
leia was put in that outfit by jabba to BE a sexual object to him, that was the point of the outfit, for jabba's gratification. the fact that the audience got the same titilation, while obvious, is secondary to the story. portman was put in that outfit by lucas' wardrobe people to be a sexual object for the kiddies, that was the point of the outfit, the audience's gratification. the audience was the only reason for the titilation.
pretty much like someone else said about the story being a vehicle for the fx vs. the fx just helping to tell the story. it's pretty much prevalant throughout. however, for the record, i am a fan of the bare midriff look and don't mind it.
i wonder if the baby luke in episode 3 is just gonna cry the whole time. watching the movies again, man was he one whiny lil bastard, and everyone still loved him as the hero!

peace
k2