I say, "No." Here's why.
There is way too much to learn in 3 years. Unless medical education is radically changed, it will be impossible for students to memorize all the unnecessary stuff they still have to memorize, complete all their clerkships, and move onto the next phase—residency training.
I do not see how medical students can choose a career path before they have had experience with rotations in all of the major specialties. I have had numerous queries from students in four-year schools who do not know what they want to specialize in even by the first part of their fourth year.
Yes, the fourth year of medical school currently is not productive. However, the amount of time needed for students to choose their specialties and interview at 15 or more different residency programs could not possibly be squeezed into the third year of a three-year program.
Some have said that shortening medical school to three years would increase the number of doctors produced. That would be true for one year when schools would graduate two classes, the three-year and four-year groups. But after that year, the same number of students would graduate from school as did so when the length of time was four years.
By the way, that year with the double graduating classes would be difficult to manage because there is already a predicted shortage of residency positions by 2015. This is due to the federal government's cap on the funding of resident positions. Graduating more than 40,000 medical students at the same time when only about 25,000 residency slots are available would be chaotic.
Here's a better solution.