Both OS options come locked out of the box. If you root your Android or JB your iOS device, the differences become far fewer in terms of software. You're left with software quality/hardware/service provider.
Phones I've owned since the iPhone came out:
iPhone 1 (4GB/8GB/16GB models)
Motorola Q2
HTC (forget name, WinMo, global phone with Verizon)
HTC Ozone
Droid Eris
Droid Incredible
Motorola Backflip
Droid 2 Global
Droid X
Thunderbolt
iPhone 4
iPhone 4S
Samsung Note (only 1 week, returned quickly)
Tablets:
iPad 1 16GB
Xoom
ThinkPad Slate Tablet
iPad 2
In my opinion, today's devices are on a pretty level playing field. Neither side feels gimped compared to the other, both offer the same things with the one exception being a few pen enabled devices on the Android side.
For me it really comes down to OS and app quality. Android is still lacking in both for my tastes but I keep going back to see how it is progressing and I have to say ICS is leaps and bounds ahead of where 2.X was when I started with Android devices.
p.s. Some people feel the need to have swappable batteries and flash memory and then you're left with only Android. However, in all the time I've advocated for both - I've never needed or used either, even with my Thunderbolt which was the quickest draining phone I've owned.
So I don't even consider them issues today. I do buy the max storage devices and never the min anymore though.
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Besides, there's no such thing as too much choice.
To the technical user: Correct.
To the average user: Incorrect.
Many people get annoyed by choice. If there was one main example of average Joe to Technical Joe I'd have to say Linux vs any other OS.