Guy Kawasaki interviews new Madison resident Penelope Trunk:

Question: Will getting an MBA or any other type of advanced degree be a good use of time and money since I can’t find a job?
Answer: No. If you can’t find a job, then you should invest in something like better grooming, or a better resume, or a coach for poor social skills. These are the things that keep people from getting jobs. Instead of running back to school, figure out why you can’t get a job, because maybe it’s something that a degree can’t overcome.
Grad school generally makes you less employable, not more employable. For example, people who get a graduate degree in the humanities would have had a better chance of surviving the Titanic than getting a tenured teaching job.