I'm looking into Scala game development, and wondering if there are any game frameworks oriented towards it, rather than Java.
I do not know what specific features of scala you'd like to see in a game lib. My gut-feel says it is better to use a well known and fully functional java engine than a new scala one. Using java libs out of the box is one of the "specific features" of scala ;-).
There isn't much in the way of game specific frameworks/engines. What does exist is largely immature though can help provide a higher level of abstraction for rendering:
I've built an engine directly on top of LWJGL over the past year. In retrospect it seems to have been a good idea. I honestly can't imagine using anything but Scala at this point (though except maybe Rust one day in the far future). I simply couldn't stand to use something as unproductive as Java or C++ again.
Not that it's a great measure of size, but my game including the engine/framework is approx 440 scala classes.
A side note: The game libraries suffer from similar problems to Scala libraries as a whole, especially in their (and in some way Scala's) relative immaturity, they're all written in their own interpretation of how Scala code should be written (something which is very diverse amongst scala libraries).