Yesterday was Grok 4.7 (pelicans) and MiMo v2.6 Flash/Pro (more pelicans). Today Anthropic released Claude Opus 5.5, and around an hour later OpenAI released GPT-6 Sol and GPT-6 Luna. It's going to take a while to get a good read on all of these new models, but here are my impressions so far.
Claude Opus 5.5, GPT-6 Sol, GPT-6 Luna, and a new price war
About this summary. This is a short, independently written summary of an article first published by Simon Willison. Cyber Security News did not report or verify the underlying story. Read the original: https://simonwillison.net/2026/Sep/22/opus-and-sol-and-luna/
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