Please don't consider using this at least until they make their own demo accessible to non mouse users (I raised the same complaint the last time this was posted, no change).
I'm all for keyboard navigation, but I'm not at the point of boycotting if somebody doesn't support keyboard-only interaction.
From what I'm told by the "business guys", making your stuff accessiblt to the handicapped is a realy leg-up on some juicy contracts.
When you click the arrow, keyboard goes up and hide the options. If you scroll or press back to move keyboard, options are gone
The landing page made a big deal out of supporting touch devices and being a HTML5 app framework; I wouldn't build anything on a framework whose own demos don't work on the most popular touch devices in the world.