Make no mistake, Mozilla has contributed a lot to the Rust project, but the particular stage of maturity you mention was achieved some years ago :)
> Mozilla and the Rust Core Team are happy to announce plans to create a Rust foundation. Our goal is to have the first iteration of the foundation up and running by the end of the year.
(Later changed to
> the Rust Core Team and Mozilla are happy to announce plans to create a Rust foundation. The Rust Core Team's goal is to have the first iteration of the foundation up and running by the end of the year.
)