We're planning to replace my 2006 macbook with either a pro or an air. Which one?... We are really happy with the macbook - it works really well considering its age, but the hardware is clearly weaker than it used to be. We don't need any software that isn't in the white macbook - the only complaints we have are: 1. it's heavy 2. the machine gets too hot 3. the battery only lasts about 100 minutes now 4. the keyboard breaks away at the edges and the machine gets dirty inside. Most importantly, the computer is in the house with a heavy smoker and a cat who takes every opportunity to sit on the keyboard. Between the cat hair and smoke, the old macbook is struggling. We are only considering a Pro because we hope it might be stronger. Is that the case, or shall we get an Air? Thanks!