backpropagation is just the chain rule of differentiation. each layer of an ANN is logistic regression, which statisticians have been and continue to be interested in.

i'm not sure your caricature of the netflix winning solution is correct: i believe it was a blending of around 25 different models (including, i think, the RBM someone pointed about above) each in themselves quite varied from one another. this is typically how these challenges are won.