What happened
X has launched Grok-powered Custom Timelines, enabling Premium iOS subscribers to pin over 75 AI-curated topic feeds directly to their home tab. X's head of product, Nikita Bier, stated Grok's AI reads every post, understands its content, and applies topic labels, moving beyond traditional keyword or hashtag signals to personalize feeds for individual users. This release coincides with the planned shutdown of X Communities, a feature that allowed user-created, member-based groups. Notably, the second position in each feed was filled by an ad.
Why it matters
This shift centralises content curation via AI, directly impacting platform engineers and product strategists by demonstrating a move away from user-generated community structures towards AI-driven content delivery. The immediate placement of advertisements as the second post in these new feeds signals a direct revenue mechanism, affecting advertisers and potentially increasing X's ad inventory. This follows Meta's recent introduction of AI feed customisation controls, indicating a broader industry trend towards AI-driven content delivery.
