Can someone please shed light to why so many ML tools and frameworks are being implemented in Python? What makes Python so special for doing ML? Personally, I would love for MS to release or support a .NET based ML toolkit. There is open source stuff like http://accord-framework.net but I would assume that it isn't as big nor complete as a framework being supported by a major corporation.
Outside of speed, I've read very few valid criticisms. What other languages are cross-platform, great lib support, delegate easily to lower level libs for perf, are there?
(FWIW, any MS based language is probably excluded from consideration depending on its cross platform ability. Many data people -- like me! -- won't use a MS based OS)