PyPy really closes the speed gap. The latest PyPy 2.5 release uses pinning to pass pointers between the C layer and PyPy greatly improving IO performance [1]. I've noticed this in a project I've been working on holding open large amounts of concurrent connections (> 100k at a time), PyPy has been completely competitive with Go, and actually using less memory. Yes, it's not as fast as a Java/C+ version, but with PyPy its more like 2-5x slower, not 10-100x slower which really changes things.

[1] http://morepypy.blogspot.com/2015/02/pypy-250-released.html