John Hopcroft and Ravindran Kannan share their draft of "Foundations of Data Science". It is clearly a more formal treatment of the topic than you will find in the other books and lectures that I mention here, but for those of you who are interested in the algorithmic and mathematical foundations, it could be a great resource. The draft covers a variety of topics, including singular value decomposition, random graphs and small worlds, clustering, belief propagation and algorithms for massive data problems.
The future of computer science is data. Have fun!