Call me a traitor. Call me weak minded to the Apple Jedi mind trick. Yes I have a 3g iPhone, the cheapest one of course.
My Treo 750, which I really liked, was starting to have some battery fade. In addition, I was using the IE browser on my Treo more frequently, with more and more contempt for IE on the phone. I had loaded an experimental browser on it a while back called Deepfish, and it was great (very similar to the abilities of Safari on the iPhone). But, Deepfish was canceled as a standalone project and will probably be incorporated in a future version of Windows Mobile.
So, I was stuck using the "diet" version of IE on my phone, which made me want to pitch it for distance at times.
I was indoctrinated to the iPhone during a charity event for the Leukemia and Lymphoma society where I took many pictures using people's iPhones as proof they made it to a checkpoint along a race. I had to fumble into menus on the iPhone, and was instantly hooked by its interface and most of all its Safari browser, even though it was the Edge version at the time.
The stars aligned and I ordered one. Below are a few observations (please note that I don't care about iPod functionality because my Zune is way, way better).
Note: If you have solutions to any of the issue or quirks, please post a comment.
Update: Added Con about querying calendars and con about attachments.