It has been long suspected by search engine optimization gurus that Google puts little to no weight on the META keyword tag. Still, many Webmasters spend a lot of time populating this tag with unique keywords for every Web page on their site.
Thankfully, to save all the Webmaster of the world time and headache, Google has made it official. In their Webmaster Central Blog they confirmed they pay no attention to the META keyword tag:
They also said they do not use the META description tag for rankings either, but occasionally they will display the META description in the summary of the page that is displayed in the Google search results. So it has some value, but still will not affect your rankings.
Even though their article doesn’t mention it, I can tell you from personal experience that TITLE tags are still extremely important to getting good search rankings. So don’t ignore your TITLE tags! Create unique TITLE tags for every page of your Web site, make them each 8-12 words long, and put your most important keywords (related to the content on that particular page) in the TITLE tag.