I was going to point this out as well, and it actually seems like a better solution. Default everyone to a modern browser with updates, and then throw them out

I was going to point this out as well, and it actually seems like a better solution. Default everyone to a modern browser with updates, and then throw them out to whatever you need to use for compatibility if needed. Chrome Frame always seemed like a nasty hack which was unlikely to get much traction in companies that haven't updated from IE6.