yeah that's an interesting question, because the Terms and Conditions
still refer to this as the only way to "opt out" of the Content
Licence granted to Google on your data. I am unsure how this affects
Premier customers, where I believe indexing=false by default, but I
guess that's covered in a separate Premier licence contract.
http://code.google.com/apis/maps/terms.html
11.1 Content License. Google claims no ownership over Your Content,
and you retain copyright and any other rights you already hold in Your
Content. By submitting, posting or displaying Your Content in the
Service, you give Google a perpetual, irrevocable, worldwide, royalty-
free, and non-exclusive license to reproduce, adapt, modify,
translate, publicly perform, publicly display and distribute Your
Content through the Service and as search results through Google
Services. This license is solely for the purpose of enabling Google to
operate the Service, to promote the Service (including through public
presentations), and to index and serve such content as search results
through Google Services. If you are unable or unwilling to provide
such a license to Your Content, please see the FAQ for information on
configuring your Maps API Implementation to opt out.
http://code.google.com/apis/maps/faq.html#tos_optout
To disable logging of information within your markers and infowindows,
specify "indexing=false" when loading the Maps API. For example:
http://maps.google.com/maps?file=api&v=2&key=abcdefg&sensor=true&indexing=false
....