We are still a long way from hitting max. Remember developers are just switching over to new engines now that they have higher resources in consoles. You will see substantial gains in the next few years. Hell "last gen" games maxed on PC look MASSIVELY better than 360 and PS3 and thats not even taking into effect what PC's will be capable of once these new engines come out.
In other words there are still massive gains in graphics remaining and once you go 4k its incredibly difficult to go back. We won't be hitting the wall for graphics for likely another 20 years.







