How to switch between VM's with keyboard.

I usually have multiple VM's open at the same time and in the past I was perfectly able to switch from one to another using the default Apple keyboard shortcut "cmd + ~" that allows to switch between screens of the same application.

After upgrading (first going through VM hell with all the instabilities, now stable on build 11994) I seem to have lost the ability to switch between open VM screens with that keyboard shortcut.

I've tried reconfiguring PD6 and my individual machines, but nothing seems to return the functionality to me.
Does any one know how to re-enable the "cmd + ~" functionality?

(Yes, I know about exposé, but it's not good/fast enough if you want to switch between VM's only)