Some Interesting sub topics are
* Why Is The Old Browser Problem Such A Big Deal?
* WHAT ABOUT IE9?
* Is IE[x] The New IE6?
* DISPLAY A MESSAGE TO USERS ON OLD BROWSERS
If all the websites agree to display some message like this, then the web would grow more faster than ever

IE provide no auto-update, when all the other popular browsers release latest versions in quick successions. So as months passes by IE becomes obsolete, even IE 9.
http://www.smashingmagazine.com/2012/07 ... k-the-web/