No prob. I'm happy Address Book does this because I've always put little tidbits about people or businesses down in the notes field. When I got my iPhone two weeks ago, one of the first things I thought about was "I hope it all syncs over so my phone is a true mirror of the info I have in Address Book". It did.
I think Leopard's new Mail notes will sync with the phone too. I believe we'll see a somewhat major iPhone update upon Leopard's release because I believe there were some Leopard-specific functions meant for the iPhone but they got put on hold when Leopard was pushed back to October.
That's my take on it, anyway.