I certainly hope it's not GPT-5. This model struggles with reasoning tasks Opus does wonderfully with. A cheaper GPT-4 that's this good? Neat, I guess. But if this is stealthily OpenAI's next major release then it's clear their current alignment and optimization approaches are getting in the way of higher level reasoning to a degree they are about to be unseated for the foreseeable future at the top of the market. (T…
This aside, I agree with you that it does not feel like a leap, more like 4.x.