Buried inside the Android Lollipop Developer Preview was an updated Google Camera app (2.4.008), complete with Material Design elements. It was nothing too flashy. Just some new icons and animations to complete the already very minimal look.
Today, this update is now officially rolling out to the Google Play Store and for the most part, is exactly what we saw in the L preview. You can either find it waiting for you in the Google Play Store right now, or by downloading it here.