Indeed it is. Compiling took 9000s on a 2GHz Dual Core Athlon with 2GB RAM. Don't even try to compile it on a machine with 1GB RAM, your system will start trashing heavily and finish sometimes between next week and never. </rant>

But after downloading the binaries, I have to say: Wow! One of my naive project euler solution is about 3-4 times faster than it was using Psyco. Absolutely impressive. (Numbers: ~66s Python 2.6, ~8.6s Psyco, ~2.8s PyPy)