Keyword density plays a vital role in overall rankings. It is not as cut and dry as it once was.
Today the ideal density varies from industry to industry, phrase to phrase. To find out what density you should aim for, take the top 5 or 20 search results and see what percentage those sites are using. In most cases you will find that the majority of these sites have a very similar density to one another, and this average density is a good estimation of what you should aim for.
Body Text and Keyword Placement:
The location of relevant text on your site will help establish the overall importance of your target phrase. While you don't want to overwhelm the engines and site visitors with a bombardment of target phrases at the top of the page, try to sprinkle in some instances as close to the top of the page as possible.
Synonyms:
Be sure to include various synonyms for your target phrases within your body text on your site. Google will use these synonyms to tie in the overall relevance of the page for your main target phrases, which in turn can improve your odds.


