This Friday I received a letter from USUHS saying that they had sent me their screened secondary by email and postcard, and since I hadn't completed it they were withdrawing my application, but I could reactivate it by completing the secondary soon. This was strange, since I never received the postcard or email (not in a spam folder either--I check periodically).
I had already decided not to complete it, so it doesn't really matter. Just goes to show that you can't always count on schools to notify you about important things.