I understand that customization is a big part of Android, but I have a hard time believing that 80% of people care about that. Only recently 82% of people still couldn't tell you what a browser is (http://www.cxacademy.org/only-8-of-internet-user-know-what-a...), so I can't see them customizing their OS, or even caring/understanding the details of OS customization.

Personally I hope both platforms stay strong, so we get lots of innovation.

I'm curious, is it possible to upgrade/customize the Android OS in the way you described if you don't have a computer?