Example:
# Get a list of fields that are not BLOB, OBJECTID, RASTER, GEOMETRY or GUID
fields = [field.name for field in arcpy.ListFields(service_table) \
if not(field.type.upper() in ['BLOB', 'OID', 'RASTER','GEOMETRY','GUID'])
# create a row list with default values
row = [""]* len(fields)
This will create a list object called row, where each value by default is an empty string ("").
Enjoy