I'm having the same issue with ArcGIS 10 Service Pack 1. Document properties are stored in the map template (MXD and older 9.3.1 MXT). However, when I open the MXD as a template from the ArcMap - Getting Started dialog box/template picker, the document properties are no longer there.
But, if I open ArcMap, dismiss the ArcMap - Getting Started dialog box/template picker, click File > Open and manually navigate to the MXD, then all the document properties are intact.
Shouldn't the document properties show when the MXD is opened from the ArcMap - Getting Started dialog box/template picker? Seems like a bug in the software. Any ideas on a fix?
Scott