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"The Google Base Blog announces new updates to Google Product Search.  The post explains that the product_type attribute has been added and should apply the category and values from the taxonomy listed here.  Further, the blog post states more about the taxonomy:The Google product taxonomy is a tree of categories that describe product families, with verticals (Electronics, Home &amp; Garden, etc.) at the highest level, followed by more specific product families or products within these broad categories (such as Electronics &gt; Audio &gt; Audio Players &amp; Recorders &gt; MP3 Players).While Google finds this value optional, I'd consider it pretty helpful and I'm sure others would agree.  Forum discussion continues at WebmasterWorld."^^<http://www.w3.org/2001/XMLSchema#string>
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