In my opinion, they've hit a dead end. I haven't seen anything unique in a while now. I feel most of the development of these new clients goes on around here. Regardless of where they are from, I feel that they've run into a virtual wall. By this I mean that anything that has really been thought of is already implemented and no incredibly unique ideas can be implemented because of the limitations of Minecraft.
Of course, there are Minecraft mods, which can tremendously change the gameplay, but I'm referring to hacked clients, such as (excuse how bland this is) Huzuni and Nodus. Both are clients that almost everyone has heard about, but what is making any of these clients extremely unique? All I've really seen in most of these clients (and I'm not bashing them) is a different gui and a reordered list of hacks. When you get down to it, most of these clients are basically the same thing (with different GUI's).
I realize that some clients bypass NCP and that's what separates the skidded clients from the better java devs, but other than that, you're basically paying for a different gui.

Opinions?