I don't know why the author thinks that there aren't any other parser/interpreters for .NET; I'll grant that there aren't many, but ANTLR still supports C#, and

I don't know why the author thinks that there aren't any other parser/interpreters for .NET; I'll grant that there aren't many, but ANTLR still supports C#, and I've been using fslex/fsyacc recently (found in the F# PowerPack). There's also FParsec if you prefer a parser-combinator approach.