According to Foresight News, a16zcrypto published an article saying that it has made a number of improvements to the performance and usability of its zkVM Jolt. The cost of the validator has dropped significantly: from a proof size of several MB in April to about 200 KB today, and can be further reduced to 25 KB; the prover is expected to be accelerated by about 3 times; support for the Rust standard library... and so on.