I replied below in this thread with the specific post, 6 months ago.
> After that, a top goal for us is to unify o-series models and GPT-series models by creating systems that can use all our tools, know when to think for a long time or not, and generally be useful for a very wide range of tasks.
> In both ChatGPT and our API, we will release GPT-5 as a system that integrates a lot of our technology, including o3. We will no longer ship o3 as a standalone model.
GPT-4 was a long time ago, and honestly mostly useless. But a lot of that progress was already present in the intervening models, and it's easy to forget it happened when comparing GPT-5 to the state of the art a month ago rather than two years ago.
This is hard to quantify exactly since very few benchmarks have the kind of scales where comparing two deltas would be meaningful. But if we pick the Artifical Analysis composite score[0] as the baseline, GPT-3.5 Turbo was at 11, GPT-4 at 25, and GPT-5 at 69. It's just that most of the post-GPT-4 improvement was with o1 and o3.
I replied below in this thread with the specific post, 6 months ago.
> After that, a top goal for us is to unify o-series models and GPT-series models by creating systems that can use all our tools, know when to think for a long time or not, and generally be useful for a very wide range of tasks.
> In both ChatGPT and our API, we will release GPT-5 as a system that integrates a lot of our technology, including o3. We will no longer ship o3 as a standalone model.