I love it when someone writes an articulate, non-inflamatory blog post with reasonable suggestions on how to improve things. It's sad how rare this is around here these days.
I missed the specific suggestions on how the pypy guys could improve things - other than "do a lot of work on numpy itself as well so that it better supports multiple implementations" (paraphrase obviously). That really needs to be the side of the equation that the numpy team take hold of.
I don't think Travis is suggesting to the pypy people to do all the work, but rather contribute to the discussion to help the numpy community as a whole for a way forward that makes it easier for both pypy and numpy own needs.