I want to give everyone a heads-up on a change made to MASON tonight. SimState.start() now pulses the random number generator 1249 times before running the simulation. As a result, simulations you had previously run with specific seeds will have different outcomes than before.
Why do this? MersenneTwister initially returns the values used to seed it initially via its Knuth seeding generator. These values are okay but not fantastically random. After you pulse it about 624 times, these values are replaced with good solid MT numbers. I'm pulsing it two rounds plus one extra (1249 = 624 * 2 + 1).
Also in case you're interested, MASON's doLoop() method now supports running multiple simulations in parallel at the command line. I'm getting pretty good speedups with it.