Hi Wasfi,
The update can be deployed via GPO or other software deployment frameworks.
Alternatively, you can also have the end user notified when a new recommended release is available. This is done with the "Prompt end user for update" setting under Connectivity > Agent Settings. With this option, the end user is notified of a new recommended release, and if they click "Update", the agent is updated. It does not force the WSS Agent to be installed.
More can be found here.