Thanks for the response, mcl. I'm in the same situation, and am working on emailing all of the Program Directors - and CC'ing the Coordinators - with my update. Writing personalized emails to each PD is getting very time consuming, though, as I interviewed at about two dozen programs. I end up writing about how much I liked visiting their program, etc. etc. It takes forever.
Does anyone think it would be acceptable to write one (professionally worded) form letter about my update and send it to multiple programs? I was thinking I might be able to get away with the generic-ness of this, if it comes across as being a professional business letter kind of thing. After all, I just want them to know this one simple fact about me - I never really intended this to be my time to profess love for programs, etc. Any thoughts?