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).

Pros:

• Now with Exchange Active Sync (EAS), see cons section for some quirks with EAS
• EAS means security policy pushed from Exchange server, ability to remote wipe if lost
• Safari browser rocks!
• Overall Interface is excellent
• GPS and Google maps integration
• Camera is pretty good, interface for pictures is excellent
• Good Facebook application add-in
• Haven't had issues with it unlocking keys randomly in my pocket like I did with a "key locked" Treo
• Better interface to read emails than on the Treo, especially expanding the reply list.

Cons:

• Battery life, can't make it an entire day even with Wifi turned off
• I miss Voice Command!!! I got used to not taking my phone out of my pocket/holster and using voice to call someone and it telling me who was calling.  This might be coming in the near future from the application store.
• Can't sync individual folders with EAS, it is "last 200 of items".  I have a folder with all my travel plans and it usually isn't in the "last 200 items"
• Calendar sync is screwy.  Even though I accept an appointment in Outlook, the phone insists on me accepting it again.
• Can't query other's calendars
• Attachments aren't automatically downloaded, only when you click on them 
• Some applications from the application store are deemed "too big" so you have to use iTunes to download them.  I have an all-you-can-eat data plan, why can't I use my 3g connection?
• Smudges, grease spots, makeup (not mine of course).  All inherent with a touch screen, reminds me of the old TMo XDA
• One handed navigation was a Treo trademark, and still is.  Apple can't match its one-handidness
• Can't flip things like email on its side for reading.  Only browser and camera seem to flip on their side.
• GPS isn't real GPS.  I believe it must use cell towers or something because it isn't nearly as accurate as my Garmin.  Probably a fix in the future...

Verdict:

• The browser alone is worth it, I can live with all the quirks
• Apple needs to actually pick up a Windows Mobile phone and use it like millions of WinMo customers have been for years.  Take some notes, and refine the experience more on the iPhone.
• Where can I get an extended battery?  Oh wait....

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.