A post titled "Humans are Faster than Computers" over on the Return Customer blog made me think. I completely see his point - far too much automation is dumb and irritating and simply gets in the way. But let's think about his scenario.
Firstly, the person he was asking knew the book he wanted. Had they not, increasingly likely with the ongoing explosion in customer choice, they might have had to go look it up on a computer anyway. Even so, perhaps the employees knowledge of the store layout would probably have given them an edge (though a well designed application could have mitigated this with directions, maps, perspectives etc). But his core point, that personal interactions have real value, is a true one and one that can be supported by computerization.
Decision management is key in both cases. Automating the decisions involved intelligently and supporting the decision making of staff who are interacting with customers really matters to customer service. Customers who self serve want to get stuff done - to take action - and thinking about the decisions involved makes this smoother. Understanding the decisions a staff member makes - offering a deal, upselling, cross-selling when something is out of stock - and supporting those intelligently can make every staff member seem experienced and knowledgeable.