To the OP :
I don't see myself leaving iOS, I've invested enough in it (my library in iTunes, iApps, etc) that I don't want to bother with re-getting some of that stuff.
For me, it's been a good ride. And most of the apps I've gotten have been well polished.
#1 consideration for you should probably be this : If you don't get an iPhone, what carrier would you go with? And from that, how does AT&T compare to them with reception where you are?
For me, AT&T has been, at worst, alright. Usually pretty good to me in my area - but that does seem to vary with AT&T and geolocation.
1. Hardware LED indicator that lets me know when I've received an email, text, call, etc.
Some like it, some don't, and that's more of a hardware vs. hardware arguement, although no iOS device will have it, admittedly
Two screws vs a plastic back which is made to be removed and replaced repeatedly. I can go to t-mobile and buy a spare battery and install it without voiding my warranty. uCan't.
My battery life is fine - why would I need to swap it out?
Like all apple software, itunes sucks balls if you don't have a mac. That is a plus in my book. I don't need ANY software to sync media or contacts to my phone.
If iTunes is sucking balls on my pc w/ XP, then I might actually move to a mac, as I think it runs pretty awesome as it is

The only thing the phone really needs iTunes for is a) Syncing music, b) backups, c) iOS upgrades. Everything else that I care to sync (contacts, calenders, etc) can sync over the air. And for music, I've enough stuff I like having a media manager in between my phone and my library.
You obviously haven't seen a captivate/vibrant in person. No comparison. Captivate/Vibrant is the nicest screen on any cell phone. There's a reason that all the manufacturers are trying to get the super AMOLED and can't. Drop by the AT&T store and check it out for yourself.
No problem. You were right about the ringtone thing.
I will say one thing - the ringtone thing isn't blatently obvious on the PC version, at least, but it's also not complicated (5 steps, max, IIRC)
Already addressed these issues. Good luck without your itunes, bud. Uncle Steve has you by the short&hairies
Ah, we refute your "iTunes sucks" line, and you find a way to dismiss by bring up a different complaint *rolleyes*
Market apps get checked. They just don't get removed unless someone influential has a serious issue with it. Even then, the app can still be downloaded outside the market. iPhone loses, accept it.
Like that virus app they removed?