Microsoft recognizes that it will be difficult to have all sites use the latest HTML and CSS specs that are found in IE8. To accommodate the web sites that cannot be converted at this time, they've created a work around. There are two options: a) you can modify the config in IIS 7 or b) you can add a new meta tag to your page headers. More information about this can be found by visiting http://support.microsoft.com/kb/952030.