Google is actually pretty fast, maybe too fast. The problem (delayed OS updates) has more to do with the manufacturers. Most are/were mainly hardware companies so they don't have a good experience of what it means to take care of your customers in a software way. They still think that a super highly clocked multi-core CPU or a big ass screen matters more than proper and timely software updates and enhancements and long term customer bindings (if that's the right word
This is where I see the problems caused by fragmentation:
-For end users: really long delays for OS updates, if they're coming at.
-For manufacturers: lots of different OS versions to support (security updates, front end customization,...) during a product life cycle. And the amount of different devices doesn't make it easier (hardware fragmentation).
-For developers: lots of different SDKs for different target platforms, limitations of older (but still widely used) OS/SDKs, a lot of different screen sizes and hardware configurations. It simply requires more time to get an app (or an iOS port) running on Android because of this. And in the end, the Android Market doesn't really accept paid apps that well. Most customers think/expect that software is free.
Have you ever developed for iOS and Android? It's like night and day, even for simple apps.
Android provides a good but clumsy way of developing relative layouts. That's why most "normal" apps scale very nicely on all those different screens. However, once you start using more graphical UI elements or even full screen images, things get complicated/annoying quickly. It's not impossible to do it but it requires a lot more effort than for iOS.
This is not meant as an Android hater post. It's just my opinion and based on my experience.
I know you like the openness of Android but exactly that can also cause major headaches for the involved parties
No doubt. I'm not saying they're only the victims here. They responsible as well by producing so many different devices and custom front-ends.
But Google is also partially responsible by making the OS so open and hammering out the major releases so quickly. By the time most devices will finally get Android 4, the next version will be out already