Updates
Added the following new properties, methods, events and constants to existing objects.
* Added the ability to query for a feature count to the QueryTask and FeatureLayer classes. These new methods only work for layers published using ArcGIS Server 10 sp1 or greater.
The legend supports the following layer types: ArcGISDynamicMapServiceLayer, ArcGISTiledMapServiceLayer, FeatureLayer. If the layer is an ArcGISDynamicMapServiceLayer or ArcGISTiledMapServiceLayer created using ArcGIS Server 10.01 or higher the legend is generated using the REST Map Service legend resource.
http://mapservice-url/legend
If the layers are version 10 or lower the legend is created using the ArcGIS.com legend service. In order to use the ArcGIS.com legend service your map service needs to be publicly accessible and your application must be able to access ArcGIS.com.
Can we get a new local installs for 2.1 under Concepts -> Inside the API -> Frequently Asked Questions -> Can the ArcGIS JavaScript API be installed locally?
Thanks!