I had the very interesting opportunity to respond to the hypothetical question “How hard would it be to move from FirstClass to [a hosted Google mail solution]?” The answer was a simple “much easier that you think” and a simple search through the myriad of Google help pages revealed this meta-page by Shay_Smith that details the process itself and also links to others with the same experience.
This site is a hosted by Google Sites for the David Douglas School District in Oregon and contains lots of great information about Google Apps for Education. There is even a contact link for Shay Smith that I think I will use to ask some follow up questions in the very near future!
Aaron Tyo-Dickerson 