To use Articulate Presenter '09 with PowerPoint 2010, you must have the 32-bit version installed. Presenter ‘09 is not supported in the 64-bit version of PowerPoint 2010 (the Articulate menu will be missing).
Microsoft has released 32-bit and 64-bit versions of Office. Microsoft recommends installing a 32-bit version of Office 2010 on BOTH 32-bit and 64-bit supported operating systems.
Microsoft recommends installing a 32-bit version, because existing Office extensions, ActiveX controls (like Flash), third-party add-ins (like Articulate Presenter), in-house solutions built on previous versions of Office, or 32-bit versions of programs that interface with Office will not run in a 64-bit version of Office.
To review the recommendation from Microsoft, please see the following TechNet article from Microsoft.
Microsoft has acknowledged that Click-to-Run versions of Office 2010 can interfere with add-ins (such as Articulate Presenter). Therefore, you should avoid installing a Click-to-Run version of Microsoft Office 2010. For more information and to determine if you have a Click-to-Run version of Microsoft Office 2010, see General > PPTA file does not get created when using PowerPoint 2010 and prompted to upgrade presentation.