It's fair to say that Android went through some chaotic years in the beginning. The pace of development was frantic as the operating system grew at an unprecedented rate. An as-yet undetermined future led to decisions that were made to conform to existing hardware and architectures, the available development tools, and the basic need to ship working code on tight deadlines. Now that the OS has matured, the Android team has been giving more attention to some of the components that haven't aged quite as well. One of the oldest pieces of the Android puzzle is the Dalvik runtime, the software responsible for making most of your apps run. That's why Google's developers have been working for over 2 years on ART, a replacement for Dalvik that promises faster and more efficient execution, better battery life, and a more fluid experience.
This will be one of the defining changes in Android over the coming years. Android 5.0, perhaps?