OpenAI has updated its GPT-4o model by improving its intelligence and personality, CEO Sam Altman said. This comes along with a move to double the hourly usage limits for GPT-4o and GPT-4-mini-high models for ChatGPT Plus subscribers, following feedback from high-usage customers. The GPT-4 model will be removed from ChatGPT as the platform will fully transition to GPT-4o model.