Originally posted by Azronger
Quote for scripts being G-canon?
The database does indeed have a canon field for each individual entry and for sources, though the canon level of the entry would overide the canon level of the source since it factors in other sources associated with that entry. When determining canon levels for individual entries, anything in the films and from George Lucas (including unpublished internal notes that we might receive from him or from the film production department) is considered "G" canon.- Taken from Keeper of the Holocron Blog
Given that Lucas had a hand in the scripts, it applies.
Except for ESB, though it'd be in the Canon anyway.