This was a well-deserved award to Angus Deaton. As usual in the last few years, Tyler Cowen and Alex Tabarrok have timely, well-written explanations of the award. In the spirit of specialization, I refer you to them, where you will also find links to many other sources.
Tyler Cowen’s write-up; Alex Tabarrok’s write-up.
ADDED 2015-10-14: The Economist has a very good write-up, too.
The curious incident of DD on the Web 