I have been reading Google’s SEO report card and I realised that when most people talk about SEO they talk about rankings on the page. What we forget is that click through is just as important than position. Description Meta tags do not count in Google’s rank but:
“Including an informative description meta tag on your pages can influence the quality of the snippets shown in search results.”
We also need to keep in mind that Google will highlight the search term in the text (“Keyword highlighting”) when it displays the snippet. This keyword highlighting helps a user select a search result.