On Windows XP SP3 testing VM with Outlook 2007 the Save & Send function for Visio Standard 2010 ThinApp is working fine. I am now tracking down the Outlook 2010 MUI installer issue.
Current suspect cause (from event viewer):
"Detection of product '{90140000-001A-0409-0000-0000000FF1CE}', feature 'OutlookMAPI2Intl_1033' failed during request for component '{BC5551FA-8420-403D-99D7-1EAC191169EA}'"