Over the past decade, social media has become the central space for digital communication, where personal interactions, public debates, and marketing strategies intersect. The integration of artificial intelligence (AI), particularly generative AI, has accelerated this process, enabling the creation of texts, images, or videos in seconds with quality that rivals human production. This fusion of social media and AI not only multiplies opportunities for creativity, personalization, and reach but also raises new concerns about the credibility of information, the spread of misinformation, and the building of trust. The literature highlights this duality: while some authors warn of a possible “information apocalypse,” others emphasize that fears tend to be exaggerated, underscoring the importance of digital literacy as a response. In marketing, generative AI presents additional challenges. Despite increasing efficiency and personalization, it can compromise the perception of authenticity and weaken brands’ relationships with consumers. This chapter aims to critically analyze how AI is reshaping social media across three interconnected dimensions: information, bias, and trust. Therefore, a balanced view is presented that recognizes AI as a tool for innovation and a potential source of distortion. To analyze technological solutions in conjunction with regulatory frameworks and ethical principles is necessary to reinforce digital literacy.