There was quite a bit of commentary on the Jan 27 post ...
http://lesswrong.com/r/discussion/lw/n8b/link_alphago_mastering_the_ancient_game_of_go/#comments
tl;dr: reactions are mixed.
My personal reaction is that it is surprising that neural networks, even large ones fed with clever inputs and used in clever ways, could be used to boost Go play to this level. Although it has long been known that neural networks are universal function approximators, this achievement is a "no, really."
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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