I think that Joscelin already figured out what's going on, but if anyone else is experiencing something similar to this, note that you may have filtered to either only viewing your geotagged synths or only your geotagged stitched panoramas by clicking the word 'synths' or 'stitched panos' along the lower edge of the screen when viewing the map.
Compare this to how you can filter results on the current site's 'Explore' page ( http://photosynth.net/explore.aspx ) by:
Only Photosynth 1 photosynths
All stitched panoramas (ICE + Photoshop + Mobile Apps)
Only mobile panoramas
Only Photosynth 2 photosynths