Keyword Density is one of the important On Page SEO factors.It is a value measured in percentage i.e the number of times a keyword displays on a page to the total number of words that appear in a page.For SEO, keyword density is used in order to determine if a web page is relevant to a particular keyword.
However though there are other factors which search engines concentrate on to determine relevancy,keyword density also needs to be given its due importance while performing On Page SEO.

Most people trying to optimize their site to get rankings and traffic find that they succeed fast in the case of Google but have a hard time when it comes to MSN/Live Search.

One basic reason is the difference in ranking algorithms of MSN and Google.From some of the threads posted in the best seo forums related to this topic,here are the major points for better ranking in MSN.

1.Ensure that the domain/website has several backlinks i,e focus on the quantity of backlinks.
2.Change the site contents by making sure that their content is fresh and unique always.