heres a quick smartphone history of mine:Blackberry 8830->8330->9530->8330(9530 storm sucks!)->Bold 9000-> iphone 3g->iphone 3gs->mytouch 3g(unlocked)->iphone 3gs->motorola droid->droid incredible->iphone 3gs->iphone 4-> samsung captivate->samsung fascinate->Motorola Droid X-> iphone 4->samsung nexus S-> htc inspire->iphone 4(still using today)
I have bought and sold many smartphones as you can see i have a personal line on AT&T and work line was on VZW, i tried many phones blackberries, androids, i played with a pre plus of a friends never owned though and have always gone back to the iphone. The truth is the iphone can get boring i love apple products build quality is superior and issues are nonexistent at least in my personal experience. While the iphone interface can get boring as hell it is the best all in one device for work/media/games/web/email/communicating. AT&T has been great in my area so call quality is no issue.
I like the thought of android and the vanilla devices are great (droid/nexus 1/s) but the skins and fragmentation seriously hurt it. i remember when worms(the game) came out on android my droid x could not play it but according to reviews the evo could and then the nexus S could. While there were differences to the phones the power were relatively similar and all released in the same year. Android is great for hackers and i had fun rooting my extra android phones for myself or friends before selling them but when hacked with custom roms they often proved unstable and i need my phone on me 24/7 for work so random reboots are a no go. But android has potential in the future i will keep my eye on it.
Blackberry's were once the primary corporate device but they are on their way out the push email for any account but the email quality is not the same.
if you need a keyboard get a blackberry if you need an all in one device go iphone.
I have left the iphone many times and have owned every iteration on launch day and after my straying i return home to the stable secure iOS platform the apps are superior the integration with my macs is amazing i love being able to sync bookmarks calnedars, music videos and tv shows for flights with one click. All of this is possible on android by dragging files onto the sd card if you have ripped dvds using something like handbrake and i do this when i can it is nice to be able to have an all in one ecosystem for media and apps.
plain and simple i love my iphone and until android does away with fragmentation it wont get another look from me. i will be staying where i am. So yes i am a very happy

Customer.
Sorry for the rant im done now.