mxd = arcpy.mapping.MapDocument("CURRENT")
title = arcpy.mapping.ListLayoutElements(mxd, "TEXT_ELEMENT", "title")[0]
lyr1 = arcpy.mapping.ListLayers(mxd, "Layer1")[0]
lyr1.visible = True
title.text = "Title for lyr 1"
lyr1.visible = False
lyr2 = arcpy.mapping.ListLayers(mxd, "Layer2")[0]
lyr2.visible = True
title.text = "Title for lyr 2"
etc.