Earlier today, the trial page for AutoCAD Civil 3D 2012 (usa.autodesk.com/civil-3d/trial) was allowing downloads. The only file that would download was the 32 bit version of Civil 3D 2011. This was raising many questions for our group, as well as on other forums.
This was a mistake. The page went live too early. Civil 3D 2012 is not ready for download yet, but will be in the near (I can't say when) future.
I don't believe that information has been made public yet. When you can get it, you'll receive an email (well, your Autodesk contract admin will).
You'll probably find it on your subscription page first, based on past experience.
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