I think we can say that this study provides further support for the hypothesis that humans and chimpanzees should be in one genus, rather than two different genus' because we not only share extremely similar genomes, we share similar generation time.
For the first time, we've shown that the difference in the rate of molecular evolution between humans and chimpanzees is very small, but significant, suggesting the evolution of human-specific life history traits is very recent.
This study provides further support for the hypothesis that humans and chimpanzees should be one genus, rather than two. We not only share extremely similar genomes, we shared similar gestation times until recently in the evolutionary time scale.
Even though mutations per se may arise in fewer numbers in humans than in chimpanzees, those that matter will quickly spread. Mutations that are advantageous to the human, such as intelligence, probably are under strong natural selection.