Meta's stock has surged over 30% in September 2026 on the back of its Muse personal AI assistant's rapid adoption, which quickly topped app charts and validated the company's heavy AI investments. Recent product launches on September 23—including a palm-sized Muse gadget and updated smart glasses—drew further analyst upgrades and price target increases, shifting sentiment from AI spending concerns to growth optimism. Earlier legal settlements removed overhangs, while strong ad revenue trends and AI-enhanced features continue supporting momentum into the September 28 close, though short-term profit-taking remains possible amid the steep rally.