I am using it daily in my job already...code examples, debugging, best practices, idea generation, etc. There is definitely a correlation in the quality of response and the quality of the prompt. Ask generic questions, get generic answers. But ask detailed, specific questions and get detailed, specific answers.

I think what has surprised me is how useful it already is in v3. Sounds like v4 isn't too far out either. Give this thing 5 years and it feels like we are going to be living in a completely different world. This is going to be an accelerant to so many things...good, bad, and unexpected.