This is the best talk I have seen in machine learning:
YouTube - The Next Generation of Neural Networks
This Google Talk, released last December, is by a highly-acclaimed machine learning professor,
Geoffrey Hinton, who is at the University of Toronto. His citation count is over 1,000:
Geoffrey E Hinton - ACM author profile page
BTW, his most popular recent paper:
Restricted Boltzmann Machines for Collaborative Filtering (applied to
Netflix Prize)