This article explores the transformative impact of generative AI on customer experience personalization across industries. The article shows the theoretical underpinnings of generative AI technologies, contrasting them with traditional personalization methods while highlighting the substantial performance advantages of AI-driven approaches. The article shows key applications in customer engagement, including conversational interfaces, dynamic content generation, real-time recommendation systems, and cross-channel personalized experiences. Through detailed case studies of major enterprise implementations, the research demonstrates measurable business outcomes across telecommunications, retail, and financial services sectors. The article analysis addresses critical challenges including bias mitigation, privacy concerns, content authenticity, and regulatory compliance requirements. Finally, the article identifies emerging trends in enterprise AI personalization, strategic implications for business competitiveness, and evolving customer expectations, providing a forward-looking perspective on the future of customer experience technologies.