(A lot of the metadata data is provided through third parties. For example, walk scores are provided via... well, Walk Score, a Seattle startup. http://www.walk

(A lot of the metadata data is provided through third parties. For example, walk scores are provided via... well, Walk Score, a Seattle startup. http://www.walkscore.com/professional/walk-score-apis.php http://www.walkscore.com/professional/walk-score-apis.php)