Graphics used for navigation really suck as far as accessibility and SEO. But if you're using a cool CSS image replacement technique, then you are a very cool webmaster indeed, and I applaud your efforts. But there are many who don't use such accessible techniques (which help greatly in SEO as well) - and as a matter of fact, those types of websites are the ones who use flash for content, navigation, etc. Now, I love eye candy as much as the next guy, and I point you all to CSS Zen Garden for excellent ideas and examples. But if you're not a CSS guru - or simply don't care... Let me tell you - you are committing Overkill suicide on your website!