Rand Fishkin discusses how SEO has evolved and which tactics marketers should embrace or leave behind. Key changes include more complex ranking algorithms using more user data signals, personalized search results, and less direct traffic data. Tactics to leave include building keyword-targeted pages with minimal unique content, acquiring links through directories and guest posting, and expecting social shares alone to boost rankings. Tactics to embrace include creating uniquely valuable and helpful content, earning links editorially, using social media to expose content, and measuring ROI through attribution models and search traffic to pages.