GPT-4 is out. There's also a LessWrong post on this with some a lot of discussion. The developers are doing a live-stream ~now (yesterday).
And it's been confirmed that Bing runs on GPT-4.
Also:
Here's an image from the OpenAI blog post about GPT-4:
(This is a short post.)
Scroll down to page 82. No spoilers.
Also, I've noticed that MacAskill's book in bibliography - but just as a general reference I would say. Haven't spotted any other major philosophical works.
I see it's indeed page 83 in the document on arxiv; it was 82 in the pdf on OpenAI website