A while ago, it was announced that Japan would be getting a new Classic Controller. This still hasn't happened - it'll be released in August, and they've already announced a differently coloured one for release on the same day - but it's apparently already clear that it will be released elsewhere as well.
The Classic Controller Pro has been spotted at E3, thus heavily indicating it will be released in at least North America. Knowing Nintendo though, it should also be released in Europe and Australia.
The Classic Controller Pro functions exactly the same as the old Classic Controller. The only real difference is that the four buttons on the top are now all shoulder buttons (instead of two of them being slightly smaller and wedged in near the center) and there's two grips so you can hold the thing like a GameCube controller.
Of course, no official announcements about its western release have been made. Japan's getting it in August, so it would make sense to release it elsewhere not too long after. If anything is announced, naturally, we'll tell you.