I have extremely little time at the moment and so no time to work on Dolphin right now. Don't expect any progress for a while, at least not from me.
Anyhow here are some answers:
Linux Version: Nope, at least not anytime soon. The graphics plugin depends on Direct3D9 since it's the superior 3D API. OpenGL is such a mess in my opinion, and I'm writing the graphics plugin
Speed: The only thing I can say for sure is that it can become quite a bit faster but don't expect to play Wind Waker realtime on today's computers.
About the chinese DLL problems: The next version will probably be compiled with #define UNICODE so hopefully these problems will disappear.
I can't make any promises if and when anything of the above will happen. If we have the free time and regain motivation, it will happen, otherwise not. Dolphin is just a free-time project for fun