I'd like to know that myself. I'm pretty sure homebrew should be okay (for the most part, and when it's not, just "brew update" it), but am not 100% sure. Sadly

I'd like to know that myself. I'm pretty sure homebrew should be okay (for the most part, and when it's not, just "brew update" it), but am not 100% sure. Sadly I don't remember what happened when I upgraded from Snow Leopard to Lion, and homebrew's homepage on github doesn't say much about the transition.