[alexanderfinn]

Your question actually contains a bug portion of the answer :) User experience is not limited to the the graphical user interface, it involves all the aspects of a person interacting with computer and its infrastructure. This involves hardware and software. We could've done it with just software (although it's not just UI, we had to significantly change OS internals too) but that wouldn't allow us to achieve our vision of human-computer interaction. Disclaimer: I work for Solu.