Gemini 4 Pro checkpoints have finally started appearing internally a few days ago.
This is the first ever output from the model, internally codenamed "argon". It took 2.4 minutes on High thinking effort.
It has a 256k token "output limit", compared to 64k in previous Gemini models. I also heard it will ship with a 2M context window, tho it's still not decided if they'll do it.