From your post "Update 17 Jan 2012: Of the top 100 sites most visited on the internet, 71 of them have content specifically designed for mobile devices."
-- I feel like websites with extremely large budgets (top 100) would currently be best served by mobile specific sites because they don't have to worry as much about the costs of updating/testing multiple different sites that most others do.
That being said, as the number of different mobiles devices quickly rises it will soon become near impossible to maintain a mobile site specific to every device.
Will You Pay for a Responsive Redesign? - http://blog.roveb.com/post/15394363841/will-you-pay-for-a-re...