What makes the new Maps Ad Unit stand out from traditional use of AdSense ads on a mashup page, is that the ads are geo-targeted based on the map viewport. Thus, if a user is looking at Napa Valley, CA the text ads will likely display ads for wineries, hotels, and/or restaurants in that region. The ads update as the user zooms or pans around, providing a greater level of relevance for the ads seen on the map.
Integrating the new Maps Ad Unit with your map mashup is relatively straightforward. As the Google Geo Developers blog notes:
Adding the Maps Ad Unit to your site is easy. You simply need to create a GAdsManager of style ‘adunit’. You will also need to link this Maps Ad Unit to an AdSense account. If you don’t yet have an AdSense account, sign up for an account. Once you have done so (or if you already have an account) make sure you’ve also enabled the account with AdSense for Content.
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