As of May 2024, OpenAI's latest flagship model is **GPT-4o**.

The "o" stands for "**omni**," highlighting its ability to natively accept and generate a combination of text, audio, and vision. It was announced during OpenAI's Spring Update on May 13, 2024.

Here are the key things that make GPT-4o the new flagship model:

1.  **Unified Multimodality:** Unlike previous models that processed different modalities (like voice) in separate steps, GPT-4o handles text, audio, and vision seamlessly within a single neural network. This allows for much faster and more natural, real-time interactions.

2.  **Speed and Performance:** It matches the top-tier performance of GPT-4 Turbo but is significantly faster. It can respond to audio inputs in as little as 232 milliseconds, which is similar to human conversational response time.

3.  **Advanced Capabilities:** The unified nature of the model unlocks new capabilities, such as:
    *   **Real-time voice conversation:** It can detect emotion, use different tones, laugh, and be interrupted, making it feel much more like talking to a person.
    *   **Live vision:** You can show it a live video stream from your camera, and it can comment on what's happening, help you solve problems (like a math equation you're writing), or even do real-time translation.

4.  **Cost-Effectiveness:** For developers using the API, GPT-4o is 50% cheaper than the previous leading model, GPT-4 Turbo.

5.  **Wider Accessibility:** OpenAI is making GPT-4o's intelligence available more broadly, including to users on the free tier of ChatGPT, which was a major shift in their strategy.

In short, **GPT-4o** has effectively succeeded GPT-4 Turbo as OpenAI's most advanced and capable model, setting a new standard with its focus on real-time, multimodal interaction.
