I've been using Xubuntu 8.04 “Hardy Heron” on my Macbook Pro Penryn (Early 2008 model) for several months now. Although there are few minor issues left unsolved, I'm quite happy with Xubuntu on my Mac because it simply works for me.
However, these past days, I've been considering replacing Xubuntu with a distro that hopefully has a much better hardware support out-of-the-box and could unleash the optimum performance of my Macbook Pro. --Like perhaps a distro that can magically help increase the battery life while decrease the hardware temperature when running.
At the moment, I have a short list of Linux distros that could replace Xubuntu Hardy on my Mac:
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