The problem with good keywords is that they are usually not words at all. Good SEO keywords are usually phrases, that is, two or more words strung together in a saying or idea. When you enter keywords into your meta keywords section, don’t use words, use phrases.
Why? I’ll give you two reasons.
1. There are too many single keywords
While you can use single-word keywords, you will be vying for position with the millions of other websites that also use the same keyword.
Let’s say, for example, you are writing a post about how to prepare a manuscript for ebook publishing. While you could use the keyword “ebook,” you will be up against the millions of other blog posts about ebooks, even if they are about ebook readers, ebook sales, or ebook marketing.
Read More...http://www.problogger.net/archives/2011/04/27/how-to-select-good-seo-keywords/ http://amplify.com/u/b10jlp