Mind if I take the devil's advocate role?
If a user has IE6 and comes to a site that is not coded to work properly in IE6, that user leaves and does not come back. That desciption fits the majority of the people on the web today, unfortunately. While I do agree that people should update/upgrade, I realize it ain't going to happen quickly, if at all.
Microsoft has soured me on the whole "forced obsolescence" idea, and the fact that a website must be recoded to work properly in IE8 just adds to that. It is bad enough that MS forced
their standards up the world's *** through distributing IE with Windows... but now they are wanting to change that as well.