Microsoft should stick to its guns and keep the Start button gone

The problem isn't the start button or the 'start screen' per se it is the combining two entirely separate user interfaces into one product.

I personally think that Microsoft should put up a firewall between the desktop and the metro environment. Just run metro apps in a windowed environment and give up trying to do everything through the metro interface. Microsoft is committed to Metro and its new UI Toolkit but the very poor discoverability of the Metro layer when used from the desktop is ironically hurting metro adoption for desktop users making app developers deal with a massive segment of windows that doesn't have any desire to use Metro apps.

Yes, Microsoft will have to make substantial changes and backtrack a bit but the alternative will be to maintain in perpetuity the Metro toolkit and environment for both touch and mouse environments.