While waiting for my 3G I've been researching a variety of things one of which is the number of mailboxes in Mail. My first gen iPhone only has 3 boxes; Inbox, Sent & Trash and no way to create any. Outlook on my PC that I sync with has a dozen different folders, some that I created uniquely. When I looked at the iPad at the Apple store it had several customer defined mailboxes that the salesman said show up on the iPad during the sync process.
As I'm unable to verify this in the documentation I've read or duplicate it with my iPhone I have to wonder if this is a first gen iPhone issue or a PC vs. Mac issue or other. Any insight on this?