Testing content="IE=8".
head/*/+body/**/ .test2 - target IE8
html/*/* /**/ body .test6 - filter IE8
*+html/*/* /**/ body .test7 - target IE7 and filter IE8
Listing all test in this series:
Listing tests by others with X-UA-Compatible:
From the IE blog Using The Emulate IE7 Button and The Default Layout Mode which are not accurate.