The New Minecraft Launcher won't play on Mac OSX

I've downloaded the new launcher for Minecraft 1.6 onto my Mac. When I start it up, the launher works fine, it starts up like normal, but if I press the "play" button, here's what happens: Game ended with no troubles detected (exit code 0) Deleting /Users/veronicaramos/Library/Application Support/minecraft/versions/1.5.1/1.5.1-natives-1372967572961698000

What I expected to happen was...:
For the launcher to launch Minecraft, and for me to be able to play.

What actually happened was...:
As the launcher was launching Minecraft, everything seemed to be going normal, the minecraft icon popped up, but then it closed, and I got this: Game ended with no troubles detected (exit code 0) Deleting /Users/veronicaramos/Library/Application Support/minecraft/versions/1.5.1/1.5.1-natives-1372967572961698000

Steps to Reproduce:
1. Open up the Minecraft Launcher
2. Let it load, and click play