A letter of intent should start off with an quick intro, that you were invited to interview on XX/XX/07. Then briefly explain what you found impressive about the school and that if you had garnered an acceptance, that you would undoubtedly attend, as it is your first choice school. Then explain why (if you havnt expressed it strongly why already). Follow up with any updates since the interview and anything that you wanted to stress about yourself that you didnt get to do in the interview. Finish up with a grateful conclusion, that you're thankful for their consideration of you as an applicant and then again re-stress that you would attend their school of medicine. Conclude it, Sign it, date it, and make sure you include in teh header your address, email, phone and AMCAS ID. Send it to the asst' dean or dean, not to the admissions office (make sure its someone on the adcom because it will only get lost in the office of admissions mailbox)