Hmmm... is that really the move of the year? AFAICT it's reasonably obvious, not so much because it's obvious that it wins, as that it's obviously the only move which doesn't immediately lose (at least, I, in my patzerishness, can't see any other.)
Now, continuation of the year, that it may well be, because to get from "a rook down but still alive" to "winning", Khismatullin had to pull off a few deft manoeuvres. But that first move? Not the key, I think.