This idea has been merged with ArcToolbox tool for starting, stopping, pausing, restart ArcGIS Server services.
Arcpy has a DeleteMapService function. A RestartMapService function would be very useful:
We have "out-of-the-box" ArcGIS Server web applications on our intranet which reference layers from a source .mxd. Additional polygon features are created through splitting of existing merged polygons based on an attribute change and a new merge based on the new attribute value. This is done with a Python script. After the source .mxd has been changed, the ArcGIS Server service supporting the web app must be restarted so the changes are visible. Currently Arcpy has the ability to delete services but a far more useful task would be to restart services to accomplish what I've outlined here.