"Fastest growing" is a suspect statistic even when it is technically accurate. A company can go from having one customer to three, and honestly exclaim, "We tripled our user base in one day!"

I use it in a limited get things done way as a kind of substitute for Stack Overflow as in here's my code, here's the error message, what did I do wrong? I've also found it quite handy for legal questions - asking it questions of UK law it can be surprisingly good and regular lawyers surprisingly bad in a being too busy not returning calls kind of way.

But yeah, I don't know many people using it for practical stuff.

I would say at least 95% of university students are using ChatGPT on their programming assignments.

Src: I teach at a University

I learnt to code decades ago and later studied computer science and physics. I now work in marketing more than anything (the marketing side of other things like film, tech and politics). To do that I often build websites and apps. ChatGPT is invaluable to me. I use it as a coding assistant. It can write things in languages I don’t know enabling things that weren’t possible within budget a year ago. It works because I have the technical skill to prompt it properly - writing larger pieces of code in pieces - and because I have the ability to identify errors and fix them. If limited to the raw output it would be an exercise in frustration, but as a person with coding chops I can 5x my output by providing detailed feedback and suggested approaches. It’s quite revolutionary. That said though I work with text, photos and video I find it useless and uninspiring for creative output. For me it’s purely a technical tool.