"Grok 4.2" refers to a model recognized as the successor of Grok 4.1 in a similar or greater way to how Grok 4.1 was the successor to Grok 4, so Grok 5.0, Grok 4.5, Grok 4.20, etc would count.
Models are considered released if they are accessible to some members of the public beyond a closed beta. An API-only release counts, as is one limited to payed users or users of a particular country.
See also:
/Bayesian/grok-42-xai-release (this market)
/Bayesian/when-will-xai-release-grok-5
/Bayesian/gemini-35-google-release-date
/Bayesian/gpt55-openai-release-date
/Bayesian/when-will-openai-release-gpt6
/Bayesian/claude-46-anthropic-release-date
/Bayesian/when-will-anthropic-release-claude-qZd5QEQ225
/Bayesian/when-will-deepseek-release-v4
/Bayesian/when-will-deepseek-release-r2
/Bayesian/when-will-meta-release-llama-5-6h9UypqOdp
/Bayesian/when-will-alibaba-release-qwen-4
/Bayesian/when-will-moonshot-release-kimi-k3
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