I've tried it out.... It definitely has potential, but is lacking in some very basic features such as multiple docks, the ability to move folders from the app drawer to a home screen (seems you have to recreate the folder on the home screen instead of just moving a copy from the app drawer), and the ability to scroll vertically in the app drawer (although there is a setting for the transition...left me puzzled). Also, it appears that if you delete the app drawer icon from the dock, you can't replace it! What the heck!?!
I'm still exploring it, and am sure that features will be added very quickly, but for now it's not much better than SPB.
$.02