Looking at moving to a new server shortly and thought I'd make the jump from a qmail/vpopmail setup to a Postfix one.
Once I setup Postfix to use Maildir and create the virtual users for my domain, is it just a matter of rsync'ing over the contents of each person's Maildir (new/cur/tmp)?
Thanks for any pointers.
Assuming your set up your new server to use Maildir format, and assuming you rsync to the correct destination for each mailbox, then yes, it is that simple.
Of course, you also have to configure postfix plus whatever pop/imap client you choose -- typically dovecot or courier, which is when you decide where to put the mailboxes.