I can only speak from my experience which over the past 4 months of daily use of ChatGPT 4 +, it has gone from many hallucinations per hour, to now only 1 a week. I am using it to write c# code and I am utterly blown away how good it has not only gotten with writing error free code, but even more so, how good it has gotten at understanding a complex environment that it cannot even see beyond me trying to explain via prompts. Over the past couple of weeks in particular, it really feels like it has gotten more powerful and for the first time, “feels” like I am working with an expert person. If you asked me in May where it would be at today, I would not have guessed as good as it is. I thought this level of responses which are very intelligent were at least another 3-5 years away.