Some great analysis from Paul Irish. Microsoft, you can end the misery by decoupling IE from your OS! Imagine the support cost savings! I might even start using IE ;)
IE9 and IE10 are both scheduled to be sunset (as far as official Microsoft support) in 2020. Since IE8 shipped with Windows 7, we can expect the same death date for it. Yes, IE8’s death date is 9 years from now. Meanwhile, you won’t have to worry about supporting Firefox 6 or Chrome 13 in November.
Extrapolating this, if they maintain the same policy, IE17 be released in 2019, before IE8, 9 and 10 finally die. So in a few years from now, you’ll be supporting one version of Chrome, one version of Firefox, one of Opera, (probably) one of Safari, and ten versions of IE.