Ultimately, at least IMO, no attempt to speed up python will succeed until the issue of Python's C API is addressed. This is arguably Pypy's only major barrier: if you can't run the software on it, you're not going to use it. Pyston was arguably the most serious attempt at fast python while maintaining compatibility with the API, but DBX clearly didn't see the RoI they were hoping to.
It's looking like HPy is going to (hopefully) solve this. But finishing HPy and getting it adopted is likely to be a pretty massive undertaking.
It's looking like HPy is going to (hopefully) solve this. But finishing HPy and getting it adopted is likely to be a pretty massive undertaking.