You are presenting a straw man. Obviously no one is going to do a rewrite. The question is simply this: Is it viable for a project? The answer is yes, because it's already been proven in several large-scale deployments, many of which are in governments and fortune 500 corporations.
Because this is slashdot, the answer is going to be 'no', and the reason given is going to be 'microsoft', because those who disagree are automatically just 'shills'.