Hot off the presses.  You can download it and get more details at https://connect.microsoft.com/SQLServer/content/content.aspx?ContentID=5395.  The SQL team has put together a really helpful page that shows you a diagram of what's new:

image

When you click on a box in each of the pillars, you will get a more detailed explanation of what's new. 

Learn more about July CTP improvements.

https://connect.microsoft.com/SQLServer/content/content.aspx?ContentID=5470

Learn more about live events, including web chats, regarding the July CTP.

https://connect.microsoft.com/SQLServer/content/content.aspx?ContentID=6082

-Marc