it is a bit faster and nicer than the original shade-c vsm. normally I get at least 40 fps, but it is level dependent, and there are a lot of things to tweak performance in the corresponding shader package too. I get about 30 fps with my RTS pathfinder having 490 units moving with vertex animation in a terrain only 500x500 tile sized scene. previously it was about 25 fps.
the simple blur takes only the actual pixel itself, and the 4 adjacent ones (but sampling distance can be adjusted). I made a poisson blur too, taking 12 pixels in total. probably will make a gaussian too (sample 2x5 or similar).
I used this little blog for my implementation: http://www.olhovsky.com/2011/07/exponential-shadow-map-filtering-in-hlsl/ (Boh_Havok also read it, if you check some outcommented lines in shade-c evo shaders), and read a short nvidia presentation, and some others I have not understood...