The Internet Explorer 8 User-Agent String (Updated Edition)

from IE Blog
As announced in February 2008, Internet Explorer 8 sends an updated user-agent string when interacting with web servers. Since we last blogged about the User-Agent string, the Internet Explorer team introduced Compatibility View and today, the Windows team is releasing the Windows 7 Beta. Each of these events has a small impact on the User-Agent string, as I will outline in this post.
The Trident/4.0 User-Agent String

In order to help users visit sites that block the “MSIE 8.0” user-agent string, IE8 will send the “MSIE 7.0” version information when viewing sites with Compatibility View enabled. As Scott described last August, a new “Trident” token in the User-Agent string allows your code to detect Internet Explorer 8 clients even when they are using the Compatibility View feature.
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