i was also placed on the standby list. i'll copy and paste what they said to me when i asked what the deal was with this list. it wasn't very informative so you may have gotten the same email but just in case, here it is:
"Our Standby list is not ranked. If a seat becomes available in the class, the Admissions Committee reviews those on Standby and chooses the best qualified candidate, based on GPAs, observation experience, letters of recommendation and the interview.
In the past, candidates have been accepted off of the Standby list up until the start of classes, however, the most movement tends to occur between now and April. If your status changes, you will be informed immediately by email. The most important thing you can do as a Standby candidateis make sure we have the most up-to-date file in our office.
If we can assist you with any additional questions, please don't hesitate to contact us."