Reusability is a thing that comes from your hands and not a framework. Of course, framework can influence it a bit. But we promote correct encapsulation at each layer. What exactly you think is wrong?
I'm sorry for negative comments but, what ruby and .net communities produce for JS is shit. It's even more harmful then IE6 for our future.
What's for binding parts (pages, layouts), I doubt you will ever want to use browser parts in node. So this is not the case.
And btw, we are going to implement node.js tests to use Travis very soon.
Except of using Coffee instead of JS your comment has no sense.