I agree that I would love to let IE6 rot away, but even with Microsoft's pushing of IE7, a huge number of users still are using IE6 for whatever reason. On just 2 of the sites I monitor analytics, around 15% of visits are still from IE6. Why? No idea, but it saddens me.
I still code for IE6, because it really isn't an issue for most things, and with the addition of the google IE6 > IE7 conditional code, IE6 gets a lot of the CSS and functions it normally lacks. I've debated on some sites adding in a large box if a user is using IE6 telling them they should upgrade to a modern browser, but haven't had the balls to go through with it yet.
Granted, I don't really care if a couple of cool features aren't present in IE6 because the # of users is low. However, I do try to make sure the site at least looks right and functions.