I personally believe that it takes a lot more than a degree to get the job done. It's bad enough that college students enter the workforce with little or no experience in entry level jobs. I feel that it would be even more inappropriate for someone with a grad degree and no experience.
I think that this is a good idea for MBA programs around the country to do. People who have at least one year of full time work experience will bring a much better and more qualified group of students into the program, which in turn improves the program and its quality.
You get your education to get your job. In this scenario you are asking people to get an education, get a job, then go back to school. It is very hard to adjust to going back to school after getting a job, plus your job may not allow you the time to get the MBA you want.
No I do not think it is necessary for MBA programs at universities to require students to have a years worth of work experience. I do think that it would be beneficial for the student, but does not make them a better candidate than someone that does not have the work experience.