IE9 hasn't been released yet; or did you mean, a super early preliminary build in the early stages of IE9 development which probably has little to do with how the final product will look like? We haven't even shipped a developer preview release yet ...
"IE8 scores 20/100, which is still much worse than all relevant competitors in their versions from the test's release, and has some problems with rendering the Acid3 test page."
(disclosure: I work on the IE team)