Thanks! Do you know if this format is any sort of standard? Or is it pretty exclusively used by Cacascius?
It is standard to the extent it is merely a string whose SHA256 hash is used as a private key, something fairly well understood even outside the context of this format. However, I have proposed it as a standard mainly for the purpose of making it recognizable and to allow implementers to offer the built-in typo detection, and because a shortened private key form is universally desirable for similar projects.
Does this mean that each key is loaded with 1 BTC?
Yes.