There is a good article in books on line that gives examples of "Performing Bulk Load of XML Data"

ms-help://MS.SQLCC.v9/MS.SQLSVR.v9.en/sqlxml49/html/3708b493-322e-4f3c-9b27-441d0c0ee346.htm

Yes, I sorry.  I didn't read it very closely the first time.

You can add a comment in the output file by adding a select statement in the sql script. (e.g.)

select...

The simplest way to accomplish this is by using the -o argument. 

When using osql -ofilename creates a file that contains all the output.