No need to remove. They can co-exist. The two that cannot co-exist are Photoshop CS6 Beta and Photoshop CS6. So if you participated tried the beta you would need to remove that.
Do you have to remove the beta before you can install CS6 Photoshop or will the installer see that it is there and uninstall it? What is the best way to uninstall it, if it does not happen automatically?