Part of the issue with alternative JVM languages is that there isn't a good standard way to mix them within a single application. There are various compatibility layers for calling foreign functions but nothing baked into the lower-level platform. So that forces a degree of competition and mutual exclusion.
Whereas with Microsoft's .NET CLR there's a standard calling convention supported by all the languages. So it's easy to mix and match C#, F#, VB.NET, etc within a single application or reuse libraries. So developers have more freedom to pick the best language for each problem domain.
(It looks like Hacker News filters out the Unicode sharp symbol. Why?)
Whereas with Microsoft's .NET CLR there's a standard calling convention supported by all the languages. So it's easy to mix and match C#, F#, VB.NET, etc within a single application or reuse libraries. So developers have more freedom to pick the best language for each problem domain.
(It looks like Hacker News filters out the Unicode sharp symbol. Why?)