However the below designs are very likely to happen in 3.8. Another good point to show these, is the obvious effort of Gnome Team to break the all-in-one Evolution paradigm, to smaller well defined and easy to use applications, like Calendar, Notes, Email etc.
The description of each image is easily understandable by its name.
The design work has been made mostly by Reda -0rAX0- Lazri and Erick Pérez Castellanos is the main developer.
While things are moving fast on Cloud side, Applications that are sync with online services have the huge advantage that they can manage multiple accounts from multiple providers. Even managing just 3 Gmail Accounts (3 calendars etc) in a web-browser is a very painful process.
This work is incomplete and hasn’t been yet uploaded in Gnome Live for further discussion but you always have to check on there anyway :)