It sounds very out of line of what you'd expect.
OpenAI continues to develop core AI offered over API. Microsoft builds the developer ecosystem around it -- that's Sam's expertise anyway. Microsoft has made a bunch of investment in the developer ecosystem in GitHub and that fits the theme. Assuming Sam sticks around.
Also, the way the tweet is worded (looking forward to working with OpenAI), seems like its a truce negotiated by Satya?
Apparently Microsoft already had plans to spend $50 billion on cloud hardware.
Now they are getting software talent and insider knowledge to replace OpenAI software with in-house tech built by Sam, Greg and others that will join.
Satya just pulled a kill move on OpenAI.
Not sure if its obvious that people would leave OpenAI in troves to join Microsoft just to be with Sam.
I don’t think they’ve had the will/need to have done this but they most likely already have the talent.