Mike FTW - Business Inspiration
I think that between the video shown below, the corresponding blog post about said video and his interview with Dan Benjamin on The Pipeline, I've learned more about client services from Mike Monteiro this year than any other book, blog or person.
He's not for the faint of heart, but he knows of what he speaks. And he occasionally uses a bad word (which you can probably tell by the freeze frame of the video). But he's got your (if you're in client services of some kind) best interests at heart. Plus, in the video below you can see that he's not really the jerk he likes to come across as in his blog or Twitter account.
This should be required viewing for anyone looking to enter into client services, particularly where there's creative work involved.