OpenAI's gpt-oss 20B and 120B, Claude Opus 4.1, DeepMind Genie 3

**OpenAI** released the **gpt-oss** family, including **gpt-oss-120b** and **gpt-oss-20b**, their first open-weight models since GPT-2, designed for agentic tasks and licensed under **Apache 2.0**. These models use a **Mixture-of-Experts (MoE)** architecture with wide vs. deep design and innovative features like bias units in attention and a unique swiglu variant. The **120B** model was trained with about **2.1 million H100 GPU hours**. Meanwhile, **Anthropic** launched **claude-4.1-opus**, touted as the best coding model currently. **DeepMind** showcased **genie-3**, a realtime world simulation model with minute-long consistency. The releases highlight advances in open-weight models, reasoning capabilities, and world simulation. Key figures like **@sama**, **@rasbt**, and **@SebastienBubeck** provided technical insights and performance evaluations, noting strengths and hallucination risks.