There are some drivers written and writing drivers is the eventual goal, but the first merges are taking things slowly (6.1 is just the infrastructure with a "hello world" example). Linux Weekly News is giving the blow-by-blow status updates:
Keep in mind that Rust is “conditionally merged” into Linux.
People want to see drivers written in Rust, but hardware companies, understandably, don't want to write any drivers in Rust if they couldn't be included in the official kernel.
To resolve that dilemma Rust was added to the Linux provisionally, if experiment wouldn't pan out it would be ripped out (similar story to what happened to devfs).
People were asking Linus about when that “provisional inclusion” would turn into “unconditional inclusion”, but he refused to answer.
IMHO he does the right thing: either Rust-in-kernel would be an obvious success (because people would love and embrace it) or it would be a clear failure (because people wouldn't use it much), I don't think middle ground where it wouldn't be obvious whether it's success or failure is all that probable.