Is Anthropic moving faster than OpenAI? Or is OpenAI working on something so big, that they aren't worried by being outpaced. Regardless, I feel like I am watching history in real time.
OpenAI are presently training toward GPT-5, with periodic GPT-4.x releases planned. These models take immense training resources, red teaming, etc. It'll be a hot minute before you see GPT-4.5, etc.