Fair enough, I definitely plan to add a public face to the site in the near future.
Regarding account "linkage", you might not be aware that App Engine apps can authenticate users using Google credentials but never see the credentials themselves and don't get any access to the rest of your data. Google was pretty careful about that one. From the developer's perspective I get an object that tells me your Google account ID (usually GMail address), display name, and (implicitly) that you have been successfully authenticated. Good question though.
Regarding account "linkage", you might not be aware that App Engine apps can authenticate users using Google credentials but never see the credentials themselves and don't get any access to the rest of your data. Google was pretty careful about that one. From the developer's perspective I get an object that tells me your Google account ID (usually GMail address), display name, and (implicitly) that you have been successfully authenticated. Good question though.