Does anyone know of success stories in generating Office Open XML
artifacts using XSLT?

(This is the "open" format used by Microsoft Office since 2007,
standardized in ISO/IEC 29500 and ECMA-376.)

I am looking for pointers to solid documentation of namespaces and
package structure, particularly for SpreadsheetML (Microsoft's .xlsx
format) as used in Excel 2007.

Thanks in advance,
--Paul