I'm not running IE9 yet, but other Windows 7 64bit users are using 32bit IE9 by adding a shortcut on the desktop for IE9 32bit. You can find it at C:\Program Files (x86)\Internet Explorer\iexplorer.exe
Then open the new shortcut, and download the latest Adobe Flash Player. Restart IE9 32bit to start using YouTube.
You should find IE9 32bit faster.
The new Square Flash is for preview, it's basically Beta. Steer clear till it's final release.
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