Agree that this article isn't the most descriptive, and evolutionary may not be the best of terms, but it should be noted that epigenetics has caught the eye of developmental and neurobiologists for some time as explaining much more of human traits/behavior than our DNA itself.
The human genome is composed of roughly 20K protein-coding genes, not enough at all to code for all the complexities in our body (if there was a gene for every bifurcation in our capillaries, we'd run out of genes pretty fast; in addition to the fact that there is no single gene for specific human behaviors, i.e. "aggression").
Epigenetics, in its simplest form as DNA methylation, provides a powerful solution to many of the issues of "there aren't enough genes", and explains a lot of the chaos-elements / environmental impacts on heritability of traits.
DNA methylation, by consequence of wrapping the DNA in chromatin, controls access to which genes get turned off/on by transcription factors (TF). TFs in turn are often influenced by environment, especially neonatal. If you do the permutations of which genes are on/off, b/c a TF can/can't access the DNA, b/c the chromatin is on/off = a whole new set of permutations that entail a new information code.
A good example of the impact of epigenetics is obesity. Children's propensity to obesity often has a lot due to with epigenetic influences during neonatal development. For instance, if a mother is pregnant during a famine and thus doesn't eat much, the fetus' digestive system will adapt to starving conditions through epigenetic changes in chromatin that bind the relevant genes, thus developing a "thrifty metabolism" (digests food slowly). This trait then stays through generations, and when such people move to the West, their metabolisms incline them towards obesity as their body still digests food slowly thinking they were born into starving conditions.
So long story shot, epigenetics aren't "evolutionary" in the original sense, but they are redefining how traits/behaviors (too complex to be explained by genes) are inherited/developed.