I've got over a decade of professional experience in C#, Python, and Java. I'd consider myself a Java developer before all else, yet I still turn to Node.js for proof of concept projects because certain things are just quicker to implement.

Here's the major caveat, out of, say 100+ PoC/prototype projects I've ever done, I've taken two to 'production'. I put production in quotes because they were actually internal services as part of our build and delivery pipeline. It's a major pain in the butt to monitor and keep Node.js running production-like in even remotely similar ways you would with Java, .NET, Python, or even PHP for that matter. I don't expect such drastically different technologies to be exactly alike for production workloads, but there's usually analogous ways to do X, Y, or Z.

You know where Node has been awesome? You land a project with a real tight deadline and its more of a fire and forget project (think interactive 'experience' at a major gaming conference for instance). It needs to run pretty well for a short period of time with a narrow scope of functionality, but some of that functionality is non-trivial. I absolutely love Node for that.