Flash will, if it's anything, be a niche product in 2 - 5 years and IE6 is irrelevant, as is Windows market share. The adoption of HTML5 has accelerated before our eyes with the release of the iPad and it will continue to do so. No one cares anymore about reaching users who can't move past IE6 and IE market share is in steady decline. However, even Microsoft will be supporting much of HTML5 with IE9, as a defense against Chrome. But, most importantly, Flash isn't going anywhere in the mobile world and having it on a couple of Android phones isn't going to make anyone think twice about dumping Flash.
Flash is already dead and content providers aren't going to look back. In the end, after all, it's their call -- user choice isn't and never has been a factor -- and they aren't going to pass on those eyeballs when they have a way to reach them that doesn't involve Flash.