Thank you for your comments, but they seem to disagree with my understanding of the information Microsoft put forth in
Select a Product for Lifecycle Information
I believe that my table agrees with that Microsoft info.
Note that I referred to Vista SP2 and Win7 SP1, not the original release nor earlier SPs.
Extended support is only provided for the non-home versions of Vista and Win 7. Extended support applies to all versions of XP SP3. I continue to get updates for my non-Pro XP3.