OpenAI announced several updates at DevDay, including GPT-4 Turbo with 128K context and lower prices, the Assistants API, GPT-4 Turbo with Vision, and DALL·E 3 API. These updates aim to improve performance, reduce costs, and expand functionality for developers. You can now access GPT-4 Turbo with a larger context window and lower pricing. The new Assistants API allows for more customized and automated interactions.