My prediction: Numpy/SciPy will steal a large portion of the Matlab market for scientific computing in the not-too-distant future. A GPU-accelerated Numpy along the lines of Jacket would be supremely valuable. Side project, anyone?
How does this compare to freely-available open source simulators? Especially <a href="http://sailfish.us.edu.pl/" rel="nofollow">http://sailfish.us.edu.pl/</a> which supports GPU operation.