That's just not true in my experience. We have two large corporate clients and one state agency that each require some level of IE6 support. I have a hard time believing these are the exception. I'd wager it's going to take a few more years to reach that point.
We have thousands of corporate clients and we tell them all the same thing: They can use any browser they like but it must be the latest / current version. Some of them grumble a bit but we've not lost a client because of IE6 in years.
So all of your clients (who use IE) are using IE9? I find this hard to believe, especially since many corporations are still running Windows XP, which will never get IE9.
