So $415m revenue per month, annualized $5 billion / yr. Let's say we use a revenue multiple of 4x, that means OpenAI should be valued at $20 billion USD just based on this. Then one obviously has several other factors, given the nature of OpenAI and future potential. Maybe 10x more.

Which puts the current valuations I've heard pretty much in the right ballpark. Crazy, but it could make sense.