Cherryview is expected to be released before the end of the year and will feature an Airmont processor, which is the 14nm shrink of current-generation Silvermont processors in the mobile space. When it comes to the graphics, while Valley View / Bay Trail had "Ivy Bridge" class graphics, the Cherryview hardware is based around Broadwell -- including its "Gen8" graphics. Riding off Broadwell, most of the open-source hardware enablement for the Cherryview graphics under Linux is straight forward and not too invasive.
The initial Cherryview support within Mesa is to be found in next month's Mesa 10.2 release while on the kernel side it will likely be Linux 3.16. Sitting between Mesa and the kernel is the Mesa DRM library (libdrm) code and now the Cherryview PCI IDs have been added there as the extent of the work needed there -- and to mark Cherryview as being Intel "Gen8" graphics.
Per this Git commit, the initial PCI IDs for the graphics of Cherryview include 0x22b0, 0x22b1, 0x22b2, and 0x22b3.