Yes, Aman and Koichi work very closely, the main point of difference at the moment is the method cache patches, Koichi is working on getting something similar implemented in MRI
As if the Ruby Community has more then enough resources to improve on TWO Compiler / Interpreter at the same time. Isn't it better to work together then to reinvent the wheel?
Speaking of compiler, the JIT for Ruby development has been very quiet for months.
