I had only gotten to know Frank in the past year, but it was definitely a pleasure getting to work with him. When he comped behind a soloist in our faculty combo at the jazz festival, it was like hearing one of his arrangements in real time. And even though he was by far the best-known member of our camp faculty, he was also humble and unassuming--definitely "one of the guys."
I can't think of anything else to write at the moment; I'm still too stunned. The man himself will be sorely missed; at least he lives on through his hundreds of compositions and arrangements.
UPDATE: A series of articles from the Garden City paper are now available on Frank's website.