I've recently found a useful tool for assessing how well your website has been optimized for keywords. You simply enter your URL into the density checker where it counts how many words you have on a page, and presents the most popular ones in a tag cloud. Give it a try:
Keyword Density Checker
How to avoid over-optimization is contained in a few simple guideline, which helps you analyze the results from your check. It generally says that a percentage score of between 3% and 7% is recommended. Any higher percentage than this may be regarded as keyword stuffing, something which Google will penalize by reducing your search engine rankings.
By Adam Moss