It’s often critical for WPMU sites to have excellent Search Engine Optimization – also known as SEO – to assist sites with getting good results on Search Engine Results Pages (also known as SERPs).
While WPMU already contains excellent SEO features – like nice page links, clean formatting and integration with pingomatic – it can always be improved and we’ve got several plugins to do this. And, of course, once you’ve achieved a high Google ranking, you may want to place some advertising on your pages.