This language looks pretty cool, but I do agree with your gut. The FAQ says:
"Note that not all Ceylon modules are available for both platforms. A module might be cross-platform, it might by JVM-only, or it might be JavaScript-only. Of course, ceylon.language is completely cross-platform."
Having some modules for JVM and some are for JavaScript-only would make things a little bit more confusing than if the language picked one. I haven't decided if this is a very significant thing or not.