I would recomend to read following parts of VFP 7 and 8 docs:
What's New in Visual FoxPro 7.0 http://msdn.microsoft.com/library/default.asp?url=/library/en-us/fox7help/html/newWhats_New_in_Visual_FoxPro60.asp?frame=true
What's New in Visual FoxPro 8.0 http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dv_foxhelp/html/fooriwhatsnewinvisualfoxpro80.asp

>Hello all,
>
>I'm getting ready to upgrade to VFP 8. I have an application currently in VFP6. It is fairly straightforward - all VFP tables, a DBC, reports, forms, etc. There are no plans to change the app to web-enabled, SQL backend or anything like that.
>
>Before I install the upgrade and make a mess of things, are there any "gotchas" or special precautions to take, other than the usual backups, etc.
>
>Thanks,