Star Wars merchandise and expanded universe rights will generate an insane revenue stream (Legos, Video Games, DVD re-releases. . Hasboro toys, books, etc.) on top of a new movie coming out in 2015 that will only supercharge those streams.
On top of that, you get extra bonuses such as Indiana Jones and all its associated merchandising.
Disney just bought itself a nice constant revenue stream that will keep generating golden eggs so long as Star Wars remains a core part of American culture.
http://www.techdirt.com/articles/20121018/01054720744/hollyw...