I often get asked about meta tags, keywords and other keys to get better positioning in Google. My answer is always the same – forget any tags, concentrate on the text on the page in web page terms “the body”.
Here we see a bodiless Matt Cutts from Google discussing this very subject.
As Matt says, the meta tags do matter but the body matter too.
In practice the it is best to start with the page text (body content) and concentrate on that, after all this is what your site visitors see. Then by all mean make sure that the required meta tags are completed but now that you already have your page text you can use this as the basis for your meta tags. Which, actually, is how it is meant to be. This way both body and head will match each other and Google will be happy.