Hopefully 8 will fix all the little nagging issues. Its a great platform if they fix the issues.
This is the major difference between iOS and the other mobile OS. For some reason the future Android releases are always going to be the next thing, and the hardware you bought is no longer supporting the next OS version.
Most of the times the former iOS devices can run the 'new' iOS for some years, some don't get the full thing, but anyway they can run it most of the times.
Yes, Apple has crippled some thing in the iOS releases and to certain extend real hardware limitations don't allow the new iOS releases to have all the features running.
Either way, they are forced by the market to make the features available or develop once they see those are needed.
And some of the crippled experienced we get comes from the carriers and not from Apple, Google, Microsoft, Samsung, Motorola, etc.
Apple and Google aim to serve the final consumer, while Apple always find the way to make a huge profit out of it, Google can live without making any money out of it.
Samsung and Motorola aim to serve the carriers.
Microsoft tend to serve just themselves.
As for the Apps being available on all the platforms, my impression is that they tend to be first released for iOS and then in the other platforms.
What killer Apps have been released first on Android or WP7?
If Apple manages to sell a low priced iPhone that also doesn't tie you to a data plan, they will for sure gain and maintain their share of the market. This is more carrier related than anything, as they will still get some revenue from the hardware, and the different digital stores they run.