https://blog.google/technology/ai/google-gemini-next-generation-model-february-2024/

Our teams continue pushing the frontiers of our latest models with safety at the core. They are making rapid progress. In fact, we’re ready to introduce the next generation: Gemini 1.5. It shows dramatic improvements across a number of dimensions and 1.5 Pro achieves comparable quality to 1.0 Ultra, while using less compute.

Once both have been publically available for long enough to get users, I'll run a poll asking if it's roughly as good as Ultra or noiceably worse for generic LLM use cases. I reserve the right to filter the poll results to avoid biased results.