I have two observations: A liberal-arts degree gives you perspective, context, and judgement . Contrary to popular belief, these are not innate traits. Given that we just read a very well-received essay about how important judgement is to a coder (http://www.engineyard.com/blog/2011/the-number-one-trait-of-...), it amazes me that we could just sort of forget about other ways these things can be developed.
The other observation is that people talk about being well-rounded like its an inherent good. Perhaps we should spell out why: It increases your luck surface area and exposes you to positive low-probability events.
Being well-rounded means you are better able to place new information in a meaningful framework, because you have a broader and wider set of contexts in which to cross-reference and evaluate your new information. The broader you are, the more likely it is that you can make some useful association with new information. Unfortunately, for the highly-specialized, not only do they not make those associations, but they also don't even know they are available to be made... How do you compute an ROI when so many of the benefits appear to be random?
An example. My father majored in history and english. He ended up writing law and arbitrating disputes. His history background let him understand and contextualize the people he dealt with -- where did they come from? What did they want? What did they value & why? etc... His degree ended up being very useful, even if he didn't obtain his job because of it.