The Apple iPad Pro was just announced, but it wasn't the only new iPad to be announced during Apple's keynote today. In a brief statement following the extended coverage on the new iPad Pro, the iPad Mini 4 was also officially announced.
Simply and briefly described as being an iPad Air 2 stuffed into a smaller, 7.9-inch form factor, the iPad Mini 4 will start at a price point of $399. As for the specs, it would seem that you would be able to take the specs of the iPad Air 2 and apply them to the Mini 4:
So, it would seem that the only difference between the two models would merely be its size. It's a big step up for the iPad Mini series. The introduction of the iPad Mini 4 also decreases the price of the iPad Mini 2 down to an arguably affordable $269 for the 16GB model.