Google地图的更新

我查了一下Google的官方说明，没有给出确切的答案。
http://maps.google.com/support/bin/answer.py?hl=en&answer=7103

Sources of information

Google Maps for the United States compiles information from many sources to bring you the best results. Our listings combine information from our web search results, data submitted directly by local business owners, and third-party sources such as publicly available Yellow Pages directories. Please note that we aren't currently able to share our full list of U.S. Yellow Pages sources. If you've found incorrect information about a listing and would like to edit it, you can do so using the 'Edit' feature.

The map data found in Google Maps is sourced from TeleAtlas. Similarly, the imagery found in Satellite mode is sourced predominantly from DigitalGlobe and MDA Federal. Although the frequency of updates m