I feel this is becoming more and more of an important factor for search engines. I believe that the search engines recognize, and appreciate that your website is complying with the latest in webpage standards(unlike Microsoft?s current browser). There is far less data for them to crawl when the CSS information is in a separate file. They don?t have to look at the same styling information over and over again throughout your site. Then there?s the matter of the HTML being coded tableless which also saves greatly on the bandwidth of both the search engine crawler, and your own web hosting plan. There are advantages on both your side and the side of the search engine. It never hurts to keep the search engines happy.