> For what purposes?

For searching answers? ChatGPT has pretty much replaced Google as a C++ helper to me. It can correctly decipher and explain deep, weird stack traces of C++ and succinctly and correctly explain semantics of the language that would take me hours of Googling.

> I definitely see some applications but "incredibly useful" seems like a bit of an oversell.

Define "incredible useful" first.

GPT is the new rubber duck.

Whether it be a legal document, a letter to a loved one, marketing materials, a literary essay, or pretty much any other kind of copy, using a tool like ChatGPT seems to be much more efficient at translating concepts from peoples' brains to the page.

If all the possible text in the world is a tree starting from the empty set, it's far easier to have a tool show you a chunk of text down a branch, and then backtrack, than it is to generate it from scratch by oneself.

ChatGPT has achieved the performance of a mediocre human at a very large subset of practical writing tasks. Given a prompt like "Write a grant proposal for the following research project:" or "Explain the opportunities and threats posed by the following business scenario:", it'll give a response that is essentially indistinguishable from the writing of a reasonably competent administrator or middle-manager.

ChatGPT is a bullshit artist with no real understanding of what it's writing about, but so are an awful lot of white-collar workers. It reliably emulates the shibboleths that indicate membership of the professional middle class. It isn't particularly creative or interesting, but it wasn't trained to do that - it was trained to produce maximally safe, inoffensive output. If people don't see ChatGPT as being massively disruptive, then I think they have failed to recognise the sheer proportion of working hours that are spent writing quite mundane letters and reports. Anyone who spends most of their working day in Outlook and Word should be extremely nervous about the medium-term implications of LLMs.