Fix Meta in native emacs for osx

Update
Do yourself a favor and follow the advice given on the mastering emacs blog and don't run emacs from a terminal emulator in your local environment. It will make your life easier!
I use a graphical emacs distro with emacs-live layered on top.

Original tip
The Meta-key for native emacs for osx is bound to ESC by default. You can change the key binding back to alt in the following ways:

If you use Terminal, open preferences 'Settings/Keyboard and check the 'use option as meta key' setting.

If you use ITerm, open preferences 'Profiles/Keys' and select the 'Meta' option for the 'Left option key acts as' setting.