Certainly is.
Saying that the Sony A6000 is very similar and has better IQ, but lenses are expensive, not as good but is much smaller. Not great for motorsport as there are no lenses without an adapter. But better to walk around with.
Saying that I tried the A7 at the weekend and its not a touch on the 5DMKIII on anything but IQ and weight. Just couldn't get on with the electronic view finder, glass was soft and expensive, small but hard to handle. More to a camera than the IQ and handling AF and usability is just as important. It will sell like hotcakes just disappointed they didn't put some new sensor tech in it. Still with the Dual Digic 6 there will be a small upgrade in IQ over the 70D and you get an extra native stop up to 16,000ISO. Still wouldn't shoot past 1600 maybe 3200 on one. 6400 no problem on the 5D.
Really wish Canon would have a go at a mirrorless system FF camera, or make a 100D style FF camera for travellers.