Tl;dr summary - it's a bunch of background info on why this designer at Microsoft tweeted out that WPF and Silverlight are dead, since IE will embrace and extend HTML5 instead.
He links to this article in the register that sums it up more succinctly:
He links to this article in the register that sums it up more succinctly:
http://www.theregister.co.uk/2010/09/09/microsoft_html_5/