Do you know of a good way to measure market share? I know of GitHub's and StackOverflow's surveys, but I'm not sure how well they reflect reality. There is also Redmonk.

GitHub's survey did not say much about Rust I think, despite Rust projects often having lots of starring. Rust projects might have a greater ratio of stars-to-popularity than projects in other languages, though.

StackOverflow's survey was much more optimistic or indicated popularity for Rust.

Redmonk places Rust at place 19th.