As others have said, anchor text is the most important thing. Meta data is not used much by Google, but it does help to differentiate your pages if you varry it from page to page. Yahoo and MSN use the Meta description as the description in their SERPs, so you should definitely have well written and accurate descriptions for them. Try to put your keywords in once, but only once as it can’t hurt. Don’t stuff your Meta keywords tag as that will only get you in trouble. Some of the smaller SEs still look for that Meta tag, so it’s good to have it there for them.