Microsoft Office 2010 includes a major new feature – the Click-to-Run technology.
“Click-to-Run is a new software delivery mechanism built by the Office product team. It’s based on core virtualization and streaming technologies from the Microsoft App-V team in Cambridge, MA.”
(More info here - http://blogs.technet.com/b/office2010/archive/2009/11/06/click-to-run-delivering-office-in-the-21st-century.aspx)
Unfortunately, MobileNoter cannot work with OneNote installed this way, at least currently.
If you get an error message like “The application requires that assembly Microsoft.Office.Interop.OneNote Version 22.214.171.124 be installed in the Global Assembly Cache (GAC) first.” that means your OneNote is installed with the use of Click-to-run technology.
In this case you need to uninstall it and install the regular version to be able to use MobileNoter.