Like most large development shops, we need to write apps that run on iE6+ browsers. Since IE does not use WebKit... Touch is impossible on IE right? No. Google created an IE plugin to solve this. I've tested this and it works great.
I found a great plug-in for IE6+ called "Google Chrome Frame" and it adds a Chrome frame to your application... using a simple meta tag in your Touch application will enable it (because Chrome has WebKit).
Google Chrome Frame is not new and has been out for quite a while. Currently, it requires Administrative privileges to install, but looks like Google is working on a User level installation that should be coming out soon.