What this document does not tell you is that you get free geolocation with it. This fact is hidden in the similarly named "Google AJAX API" (not missing "library"). These are common APIs for Google websites, but lookee here: Client Location (and of 2009-05-29, "New").
And the following is filled out (or is null if they can't figure it out):
Comment 2009-05-29 by None
No idea how you find time to blog. I gotta get started on that.