"Will Jones IT be setting up our Google Mail accounts and will they continue to be the same as before (firstname.lastname@example.org)?"
SHORT ANSWER: Yes :)
SAME EMAIL ADDRESSES: Yourname@yourcompany.org will remain the same. We will handle moving the email accounts and your email will not change. The one difference is that you will need to access it on a web browser (chrome, firefox, etc) at mail.google.com. I just love to say yes!!!