Adwords: Use Keywords and Placements Together
From the Google Blog:
When you use keywords in your ad groups toÂ contextually targetÂ your ads, we match them to relevant pages across the hundreds of thousands of sitesÂ onÂ theÂ Google content network. But have you ever wanted to bid more (or less) for a specific content network site you’re contextually targeting? Or write customized ad text for a precise group of pages, such asÂ news articlesÂ orÂ relevant discussionsÂ on social networks? Now you can. Read more here.