Longtime lurker coming out of the shadows just to say that you're not the only one--I did the same thing in my writing sample for Penn, that is I had "Stanford" in the heading! I blame it all on Pages, which I HATE HATE HATE (:P). But, really, when juggling 10+ documents, these things happen. I wouldn't get down on yourself so much. In case it makes you feel better, when I was considering applying to UCLA but knew that I would have trouble getting one of my letters in by the deadline, I called the department, and the person I spoke to made it seem like they are the most accommodating program ever. He said something along the lines that if an application is missing one or a few parts, they would get in touch with the candidate rather than just throw it out completely because it gives them a chance to view the strongest applications possible. It was surprising to me because I feel like most programs treat us like beggars at the door (not sure if this is necessarily true or a delusion borne out of despair and despondency ), but it sounded like UCLA is trying to approach it more like we are assets. I also did my undergrad there (ultimately why I decided not to apply) and know it's a great program. So best of luck to you and everyone waiting to hear back from them!