Before I begin, I'd like to preface by saying that I'm not an AI Engineer. I've understand some the basic maths and the basic understanding how earlier classification models could be programmed but that's about it.
What they have done so far is quite amazing
It is true, although I still use it only within the confines of the browser and mostly the get quick validation for ideas and helping me write SQL. But I cannot deny that, it's some fascinating technology. It also comes with a host of risks but much smarter people have spoken up about it.
Certain enough to build entire cities around it?
$500 billion is an amount of money that I cannot even fathom. I'd say most people cannot. What do they know that makes them so certain to bet that much money on it. What is it based on? My guess is that, the first company that cracks AGI will control everything or so they think. If something is truly that super intelligent why would it serve any companies needs? Why would it comply to any request? Not in a evil sense but rather what would stop it from saying, "Yea nah, can't be bothered, I got bigger fish to fry"?
My guess is that a truly intelligent thing would not need a lot of time to understand that it's being directed by less intelligent being and it would do what it wants to do. Not building a Todo App for Timmy over here.
There are quite a few unknowns that I'm not aware of. Frankly because it does not interest me at all not even the slightest.
What am I going to change?
Absolutely nothing. I love to write code and that is what I will do. Will it be useful? To me it will, no one can stop me from writing code, don't care if something can do what I do in a year in a millisecond. It is my life and I will completely own and face the consequences of my actions. Both positive and negative. So this news changes absolutely nothing for me. Desiderata along with my own instincts are my guide. Always have been, always will be.