I think Christof had a posting a couple of years ago with a VFP class that would allow for some formatting (Bolds, colors, etc.) of the XML so it looks "nicer" when opened. I think you can even put formulas in the XML and have Excel honor it.
Indeed. The white paper is still on our web site:
http://foxpert.com/docs/excel.en.htm
A sample program is at the bottom