Yeah, the Luke/Leia brother and sister thing kind of ruined part of the original two movies, in a way. I just showed the original version of The Empire Strikes Back to some friends on a projector, and resounding "eewww"'s echoed through the room when Leia kissed Luke. It wasn't disgusting before, but now it is. But Lucas was forced to do it because Han survived through the movie and he didn't want one guy to be disappointed. See, if Han was dead, Luke could marry Leia and there wouldn't be a problem.