To be honest, no one has ever sold me on the idea of a Mac. Yes they do have a nice pointy clicky interface, but afaik, there's nothing you can't do on them you can't do with a PC running either XP or Linux, or (my personal preference) XP + Cygwin.
That coupled with the fact they're more expensive, and will most likely be comparativly hideously expensive to repair when your house mate spills tesco value lager on it! :-) and more easily pinchable.
Tom