In an effort to improve Web users’ compatibility experience, Microsoft added a new, user-selectable Compatibility List to the IE 8 RC1. Microsoft describes the list — Version 1.0 of which includes 2,400 sites that don’t render properly in IE 8 (in other words, an “incompatibility list” – as a tool designed to “make sure IE8 customers have a great experience with highly trafficked sites that have not yet fully accomodated IE8’s better implementation of web standards.” There is a downloadable list for IE testers using Vista and another version of the IE 8 list for XP users.

Source:→ Mary Jo Foley's Blog