Don't forget that, running on the JVM with great interop means that any Ceylon program has instant access to a huge ecosystem, including not just Java libraries but also Scala libraries. I was able to use Apache Spark in Ceylon ;)
The question is: why would you use Ceylon over the competition?
There are a number of reason I can think of. You want to target node.js too; you're a Haskeller in your spare time. That sort of thing.
But the question still stands. Is there enough to prefer it to Scala, Kotlin or, gasp, Java?
Honestly, I don't know. But equally there's nothing that stands out for me. If anything this has actually made me think I should probably look at Kotlin again.