I installed Arch linux on my macbook (dual boot with Snow Leopard, I dedicated 45GB to Arch with 5GB Swap).
A small hiccup so far, but things are working out so far. I still need to set up a few more things, but basic things are set up now. I think I will write up a wiki page once I am happy with everything.
Also, I found out that my macbook’s generation is Macbook4,2 (Late 2008 model) through wikipedia.