sorry to hear you say that, sometimes i'm thinking the same thing. i would've gone for the mbp but i had'nt enough money. my main reason was durability: the macbook got too many scratches in my backpack and i almost broke the hinge once.

interesting thing is that the pbg4 fw800's manual shows two fans, so that is more probable. i suppose the 12" model is the one with only one fan.

today the 10.5.2 update arrived and although the overall graphics performance is better, i still get the weird cpu usages.. you might be right about apple being less willing to support older configurations. sometimes i feel nostalgic about 10 years of backward compatibility..

one question though: can your tibook boot into os9 natively?