The R Book, 2nd Edition is a nice read and resource just four chapters in. It is new to me to find a resource that poses so many examples of things you want to accomplish with links for explanations how, instead of presenting a core of functionality and letting you choose how yourself. Definitely a “read-as-you-need” book, and the first chapter even explains how best to utilize it in that manner.
Addendum: 2014-08-23T11:15:48-0500
Chapters 1-5 seem to be about R proper, and everything else is about applied statistics.