Google rolled out updates recently for its Play Books, Movies & TV, and Music apps — as well as a redesigned Play Store — all featuring Material Design. Lollipop is also on its way for Nexus devices, and tons of manufacturers have already promised Android 5.0 for their flagships.
As of the latest update, you can now get two new material themes for your Google Keyboard; just go to Settings > Language and Input > Google Keyboard > Appearance — from there, you can choose from Material Light and Material Dark. They both look great, and it seems that its a lot easier to type with. Try it out for yourself.