I've posted a little before but I'll formally introduce myself.
I'm an electrical engineering student at the University of Tennessee who's been an apple hater all his life. I hate the way apple does business and I would have nothing to do with the iPhone were it not for a miracle. You see I'm also an AT&T sales rep. I actually had a lady come into my store with an original iPhone with the infamous dead strip problem. She was eligible to upgrade and went ahead and bought a 3G from me. She was walking out of the store and left her old iphone on the counter. I stopped her as she was leaving and she told me to keep it. Thinking it was unserviceable, I thought nothing of it. A few days later I made an appointment at the Apple store figuring that even if they charged me the $200 to replace the screen, it was still cheaper than buying a new one. Keep in mind at this point I was using an HTC Tilt from AT&T as my company use phone, so any upgrade would have been worth the money. The genius said that my iPhone matched a series of iPhones that had the infamous dead strip problem and that the warranty had been extended to cover this. WHAT! FREE IPHONE!!! WIN!!!
So I dove head first into using the iphone and I suddenly became aware of how much better the iPhone was to use for internet browsing. I was content on using wifi at home, work, and school. However, as I started using it for various things outside these places, I realized I needed 3G BADLY. So come pay day three months later, someone was selling an 8gb iPhone 3G for $400 on craigslist. So I bought it and it was working fine. I went on ebay and sold my 8gb 2G for $300 with a boatload of accessories (I realize I could have gotten more, but I figure I'd pass the savings along to some lucky shmoe and even helped him unlock it for t-mobile using the How-To guide on this site). Even then, $100 for an iPhone 3G with no contract and on a company paid line is about as good as you can get (plus I can tether all I want to without any charges!).
At this point I had a coworker of mine add my UDID to his dev list and I'd been using the 3.0 beta exclusively until 3.0 final was released and I felt really bored with it considering I'd had all these features for months beforehand. So I got into the jailbreaking scene and I've been hooked ever since. I will never ever go back. Of course I have to be really careful to turn off all my winterboard mods and hide the jailbroken related icons when I go to work so that I won't be ratted out or confuse customers.
As for me personally, I love social media like Twitter and Loopt. I've also been a Sprint customer personally for over 10 years and I still keep that phone active because I love the service and my parents pay the bill (double bonus!). I'm also an active member of the PPCGeek community which is entirely dedicated to customer ROM and software development for Windows Mobile devices, mainly on CDMA carriers. I love both phones and each serves a different purpose. I consider my Touch Pro a workhouse or a mobiel Swiss Army Knife. I have Skyfire to load full flash pages like Hulu. I have WMWifiRouter to share my sprint connection with any capable laptop (I might be getting MyWi soon to replace this because I have a cap on my Sprint data usage). If I only had one phone, this would be the one I'd keep. However, every week there's something new on the iPhone that replaces something I do with my Windows Mobile phone.
I'll make the argument that the iPhone is still not there yet when compared to the capabilities of Windows Mobile. But what it lacks in workhorse features, it makes up for that in usability and "coolness" in spades. I'll be an iPhone user for the rest of my life.
Sorry about the long introduction but I'd like to think that I come from a slightly different viewpoint (being a WinMo and sprint fan to the death) than many users here and I think that is a testament to the wide appeal of this device and the community surrounding it.