I bought a refurb iBook G4 back in the day and had it for 2 years. No glitches, no problems, etc... It was great and my next laptop I buy will probably be refurbed.
My girlfriend got a "refurbished" 1.83GHz white MacBook a few months back. It came in a plain brown box, but other than that, I'm pretty sure it was brand new. There were absolutely no scratches or marks on the laptop, and all the accessories were new. I'll definitely be buying a refurbished Apple laptop for my next computer.
1 year AppleCare and you can purchase the 3 year extended program. Even with the extended AppleCare, you still save money over a new laptop. I say go for it!