Minecraft 1.8 mac OSX 1.6.8 - minecraft.app not running at all
I found the answer on the minecraft forums, so I'll repost it here.
http://www.minecraftforum.net/topic/36564-minecraft-on-osx-wont-open/ Thanks to
ahefner said: The bundle doesn't work because some unix file permissions get screwed up as a result of distributing the app bundle inside a zip file (versus, say, a .dmg). You can fix it from the terminal using the chmod command as follows:
chmod +x ~/Downloads/Minecraft.app/Contents/MacOS/JavaApplicationStub
Modify the above command to reflect where you unzipped Minecraft at. This will fix the bundle so that it opens when you click it.