Google Maps API の仕様変更により編集方法が変わりました。
基本的には
{{#display_map:[座標]}}
というコードを埋め込むと地図が表示されます。
マーカーを一つ表示した地図の例
{{#display_map:35.600753 139.667300}}
地図を読み込み中...
{"minzoom":false,"maxzoom":false,"mappingservice":"leaflet","width":"500px","height":"350px","centre":false,"title":"","label":"","icon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"zoom":false,"defzoom":14,"layers":["OpenStreetMap","\u5730\u7406\u9662\u5730\u56f3","\u5730\u7406\u9662\u5730\u56f3 \u5358\u8272","\u7a7a\u4e2d\u5199\u771f 1940s","\u7a7a\u4e2d\u5199\u771f"],"image layers":[],"overlays":[],"resizable":false,"fullscreen":false,"scrollwheelzoom":true,"cluster":false,"clustermaxzoom":20,"clusterzoomonclick":true,"clustermaxradius":80,"clusterspiderfy":true,"geojson":"","clicktarget":"","imageLayers":[],"locations":[{"text":"","title":"","link":"","lat":35.600753,"lon":139.6673,"icon":""}],"imageoverlays":null}
詳しい編集方法はMaps for MediaWikiの Leaflet maps に関する項目を参照してください。