It looks like you already know the answer. 🙂 It will vary from school to school. Schools that have rolling admissions will usually respond sooner, but it also depends on how swamped they are. For example, I heard from Tulane, Ohio State, and MCV within 3 - 4 weeks. The University of Utah took more than 6 months to send me ANY decision from the time I interviewed. Most schools will give you a timeframe when you interview.