It was painted on a railroad bridge on the clockwise direction of the Beltway just after you pass Georgia Avenue. As you go up the hill at Georgia Avenue, the Mormon Temple rises into view, just like in the scene in the movie when they first see the city of Oz. It looks very much like that particular shot in the film.
Guy just forgot to put in the ‘estas’, that’s all. 
Or maybe it’s a really deep question about Bush…how? HOW? HOWHOWHOWHOWHOW…?
(probably just a tagger name…most likely means nothing or sounds cool. I remember the “Surrender Dorothy” thingy as well…always cracked me up)
-XT
They got scared away before finishing “Como esta usted?”?
Ahhh … I always thought of it as Cinderella’s Castle. I had forgotten about the Emerald City.
Here’s a picture.
Here’s a picture that shows the temple as it appears from the spot on the Beltway where you could see the graffiti:
