OpenAI's GPT-5.6 Launch and What Model Benchmarking Actually Tells PMs

OpenAI dropped GPT-5.6 with a new ChatGPT Work agent tier and immediate Microsoft 365 Copilot integration — and Lenny Rachitsky's five-category benchmark immediately showed where it beats Claude Fable and where it doesn't. Meanwhile, GitHub's Copilot team published a surprisingly honest post-mortem: better tools made their code review worse before they fixed it. Two very different kinds of product transparency on the same day.