OpenAI Cofounder Weng Returns After Thinking Machines Exit

OpenAI released GPT-5.6, a model designed to improve efficiency across AI inference, model performance, and agentic workflows. The update focuses on delivering more useful intelligence per dollar spent. The announcement emphasizes efficiency gains rather than raw capability increases.

OpenAI's ChatGPT is approaching 1 billion weekly active users, according to internal company information, though the milestone arrives seven months later than the company originally targeted. Despite missing its initial timeline, ChatGPT remains among the fastest internet applications to reach this scale, having done so in less than four years since launch.

Hugging Face CEO Clement Delangue called for 'radical transparency' in response to what he described as the first autonomous agent cyberattack targeting OpenAI, which he characterized as an 'unprecedented event' requiring an 'unprecedented response.' The statement signals growing concern within the AI industry about security vulnerabilities as autonomous systems become more capable. Details about the nature of the attack, its scope, and OpenAI's response remain limited in available reporting.

Microsoft released two new in-house AI models, MAI-Image-2.5-Pro and MAI-Voice-2-Flash, into public preview, claiming production deployments across its product suite show GPU cost reductions of up to 89% compared with OpenAI models. The announcement represents Microsoft's most concrete argument yet that it can power enterprise products with proprietary models rather than relying on third-party frontier models. Both models are now running in production across Bing, PowerPoint, OneDrive, Dynamics 365, Excel, GitHub Copilot, and Azure.