Being 2-10x faster and using a lot less memory isn't impressive? I'm sure the Go optimizer still needs a lot of work. It's going to get much better. The V8 optimizer is great but we're probably closer to the limit of how much more can be done than with Go.

I think there's a bit of a disconnect here between people who work on applications where, say, a 25% reduction in CPU usage would be a big win, and people who don't worry about performance as long as their cluster isn't melting down.

Those results are from the x86-64 machine with one core (because the multi-core 64-bit machine is still running Go 1.0.3). Once Go 1.1 is realized and the multicore machine is updated, run the comparison again there. Javascript fairs even worse against Go when multiple cores are available. Gos support for parallel processing blows JS away.