I jumped from 1.6.12 to 1.8.0 I noticed that arduino.org also moved from 1.7.x to 1.8 and now has the same change log as the Arduino.cc version 1.8.0. This must be the way the dispute ends.
I brought the two IDE versions up side-by-side and there is something funny about the font in 1.8. It is especially noticable in the Preferences dialog. I guess they left us something to complain about until we get 1.8.1 or so.
As far as putting it through its paces it seems like 1.8.0 handles everything that I was running in 1.6.12 and there were some additional board choices for most of the products from Arduino.org. It doesn't have any selections for their Zero Pro, M0 Pro, and M0 boards but it looks like these can be treated as Arduino Zero boards just by reflashing the bootloader.