Enabling an Alert to be shared by the message recipients is a really effective way of getting your accurate message propagated into local Facebook Groups and shared by end users on their own Twitter accounts.
As long as you "Propagate" or "Share" your message when you create it, the share buttons on the Alert email are enabled and the message can effectively be shared exponentially.
Only share messages that you want within the public domain. Visits to the online version of your Alert email are counted and can be reviewed in the "Message History" report.
The following video show how end-users can use the Tweet and Facebook share facility within the Alert email to post and tweet your messages.