Autodesk Labs sent out this heads up via email today:
The 3D Annotation for Inventor technology preview was released in July 2010. Autodesk Inventor 2012 was not released until April 2011. This is just a reminder that although it was not mentioned when the technology preview was first announced, the technology preview is compatible with Inventor 2012.
You can download it here: http://labs.autodesk.com/utilities/inventor3da/