I am an Arts and Technology major and the focus is pretty much 100% 3D. Modeling, texturing, lighting, compositing, rigging, animation, motion capture, everything.
I also had a 2009 MBP, but it was getting pretty slow, especially when rendering.
The further along in school you go, the more complex things you will be doing. The more complex, the longer the render times. The more CPU power, the faster the render times.
When rendering animation in a mental ray rendering engine, render times can take a while. So the added CPU power is definitely beneficial.
With all of this in mind, I would say get the best you can afford. I definitely don't consider my MP overkill. Render times can always be quicker. And rendering sequences can still take hours to days.