>Would the following statement be a safe assumption? "Anything built in VFP8 will compile in VFP9"

I think it's a safe assumption if you didn't use VFP9 reserved words. You may re-check all your reports for speed and how would they look like. Also check if you used FLUSH FORCE without specifying an alias (this was a problem for us).

Other than that I don't anticipate problems. You may also review your select statements with GROUP BY.