I have received this question numerous times even though interview season hasn't even begun! There is no perfect answer to this question and, if you ask 10 people, you will receive 10 different responses. There is one article in the literature that shows no correlation between interview date and rank position: Click Here to read the article.
If you have the luxury of choice, schedule one or two "safety program" interviews early in the season. It is my personal opinion to save the best for last. I always found it refreshing, especially at the end of a long interview season, to have a terrific applicant who was a pleasure to meet and interview. When we concluded our season and ranked applicants, it was easier to remember those applicants who interviewed later in the season and I was often "fuzzy" about applicants who interviewed in the middle of the season.
The bottom line: there is no magic formula here. Stay in touch with programs (especially those in which you are interested) so they don't forget you. Don't "can" or memorize responses for your interviews and do whatever you can to stay energetic throughout the season.
Visit: http://www.mededits.com/.