The SqlFormatter is used to move values from a data reader to an instance of an object, and to move values from an instance to the paramters of a stored procedure.
Direct SqlFormatter use is not normally required, but there is a case for loading a single object with results from a datareader, checking the object, then loading the next result etc.
I will post some code to do this shortly, and hopefully this will demonstrate the usage for the read functionality.
If you let me have more details, I can also give you some code for updating storage from an object instance.
It is also good to keep in mind that using a provider class directly such as SqlFormatter creates code that is unique to Sql Server. Other formatters may implement this code in a completely different way.