I don't believe the author is 'pimping' Rust. "C#" appears five times on the page, in snippets like this:

    It seems to borrow quite extensively C# and .. I don't know how to say this politely or immodestly ... Rust. Which is flattering if true! Of course I'm biased. Also a language pluralist, and since Rust is a major cobbling-together of things we liked in other languages (ML, C++, C#, Lisp, Ruby, etc.)

It also seems like he's more generally excited about the prospects of not being limited to a small set of languages to do powerful things.

    "It's remarkable to me that in the years between, we've seen such a shift in what's considered "normal" new-language tech. F# is shipping on several platforms (whether or not M# ever actually surfaces again); Scala is considered an employable skill; C++11 has lambdas and local type inference at least, if not algebraic types or pattern matching; Rust actually exists now; and now one can rely on similar comforts in the Apple ecosystem. How delightful!"