Is this github code the 3.13 that BenF said somewhere he had given to Seeed Studio? Is there any announcement about this, or release notes? Are you (HugeMan) from Seeed Studio? Is the license the same as the 3.11 BenF code drop? Sorry for the flood of questions 
The github repo does not have any history, but I will see if I can diff it against the 3.11, and merge those changes into the gitourious tree. As long as the license is compatible, of course.
I have been thinking of making a FFT branch on gitorious, but the FFT code is non-free so it complicates things. It also seems a bit tricky to get it to build on gcc, the code uses some compiler-specific instructions, and my first attempts have failed to run correctly. Maybe Paulvzz can consider maintaining his own FFT branch, and merge in any changes from my tree as they happen. So that there is no confusion that my tree will always be free software.