List of layers by feature type

layers.py

point_layers = []
line_layers = []
polygon_layers = []

for lyr in arcpy.mapping.ListLayers(mxd):
    if lyr.isFeatureLayer:
        # Try to get .shapeType attribute from data source.
        # For XY event layers there is no shape type (it's a
        # CSV or something) so assume it's a Point layer.
        shape_type = getattr(arcpy.Describe(lyr.dataSource),
                             'shapeType',
                             'Point')
        if shape_type == "Point":
            point_layers.append(lyr)
        elif shape_type == "Polyline":
            line_layers.append(lyr)
        elif shape_type == "Polygon":
            polygon_layers.append(lyr)