I guess this question is still, remarkably, customer dependent.
I'm a student and have been for the past... well... forever. not going to finish any time soon. So I've milked the student applecare. Also, been on a series macs for the past 10 years.
Here's my recommendation in a nutshell: imacs and laptops, get apple care. Monitors and mac pros or towers, it's much more up to you.
But as a student, you'll likely want your very expensive computer to last awhile. Things happen with computers over time- the boards get old, they have faults, etc. Fans die. Screens go down. Powersupplies kick the bucket.
I've had apple care on all my computers, but have found it to be vital on my laptops because almost nothing in them is user servicable. I've now taken in 2 macbooks, a macbook pro, 2 ibooks, and an old G4 tower multiple times. And applecare takes care of them all- if of course what's going on is their problem, not mine. I'm also very aware of what's going on with my systems, so you've got to do a little bit of leg work and research if something goes wrong.
But bottom line for me is that i can't afford to replace my computer every 12 months, nor can i afford to repair it if the logic board dies and costs 2100 bucks. i just can't. I need them to last as long as possible under relatively consistent use.
Applecare is my best insurance policy to extend the life of my systems if i'm taking care of them appropriately.
my vote: without a doubt, get it.