Compatibility View list’s not enabled by default - users must opt-in to the feature as part of the first run experience or later by selecting ‘Include updated website lists from Microsoft’ at Tools -> Compatibility View Settings. You can view the list currently available on your Internet Explorer installation by typing ‘res://iecompat.dll/iecompatdata.xml’ into the browser’s address bar. This download consists of a list of sites that are most likely to be displayed better in Compatibility View in Windows Internet Explorer 8.

More info: Download