If Adobe Reader 9 doesn't want to install on Windows 7 beta for you - it didn't install on my ASUS R2H UMPC, but then it did on my Shuttle XPC desktop - and you only get the self extract part of the install and then it simply disappears, you can try extracting the package contents yourself by running the following from a command line:
AdbeRdr90_en_US.exe -nos_ne
that will extract the installation files in "%USERPROFILE%\Local Settings\Application Data\Adobe\Reader 9.0\Setup Files". If you want to install both AIR and Reader 9, run the main setup.exe, otherwise for just the Reader run the Reader9\setup.exe. Follow the instructions to finish the installation and you can remove the setup files when you're done (~113 MB).
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