Calendar wise, I really hope I will be able to accept calendar invites from the iPhone. Thats something I have really hated about the Treo. I don't always have time to sync up, and its very annoying when out and about seeing a new calendar invite come through but not even be able to see what it is, or when it is.
This drives me and my co-workers nuts, Steve if your listening ... you could get all of them to buy it if it had calendar invite support directly on the phone 😀
(I am purchasing one regardless, but will be annoyed if I can't accept invites)