It seems to me that they are trying to update the interfaces to look more similar with Google+ and make them pixel perfect across all their applications. That'

It seems to me that they are trying to update the interfaces to look more similar with Google+ and make them pixel perfect across all their applications. That's why I think it is good to see all the apps change in a short time span, which makes it easier to get over the changes. There seems to be some change regarding how they push updates and new features/designs to the world. I remember it took months of testing before they decided that the current search bar at google.com (wider and larger) was good enough. Now they really are pushing total UI revamps in 2 days.