I felt so good about how IMAP worked on my device that I needed to share a quick fact. I am coming from 5+ years with different Blackberry devices up to the Curve that was just released. In the entire time I used RIM, IMAP support was GARBAGE. No 2-way sync, all 1 way and horrible at that. Now since setting up the iPhone, well not even setting up since it did it automatically once I synced with my Mac, everything has been flawless from being able to access all my folders and everything. My sent mail and deleted mail is even synced perfectly so I can check my mail from a web browser, from Mail.app, or from my iPhone. My setup is my domain tied into Google Apps/Mail (sweet too btw) and then forwarded to my IMAP account at fastmail.fm (another good one). If anyone has any questions about my setup feel free to PM me!