Esri Maps for Office is a great tool for map-enabling spreadsheet data. And, the fact that the map and data remain dynamic, so that as the data cells change the map changes is great. A nice addition to this would be to enable the automatic updating of the shared layer in ArcGIS Online - maybe a scheduler that could be managed in Excel, for exmaple. It is a common workflow for non-GIS users to update info in Excel on a regular basis, and having that automatically populate the shared layer would be a time-saver.