The fact is, the .Net VM provides support for all manner of statically-typed, single-inheritance imperative object-oriented languages. It could potentially host C#, or Java, or Oberon or Ada or Modula-3 just fine. In other words, you can program in whatever you want, as long as it is basically C#.
The rest of the article talks about a new opcode being added to the Java VM to allow Java to be better about this.