Steve,

Thank you for your article. I would like to add my 2 cents:

- xml data-type should be and must be strongly-typed (i.e. client has to pass not just well-formed XML but also XML with a particular schema, each xml parameter in or out could have different schema);

- there is an alternative to xml data type in SQL Server 2008 it called Table-Valued Parameters.

Cheers

Regards from Down Under