The main article in the February issue of National Geographic is by science writer Matt Ridley and it's title is Modern Darwins. Here's a quick summary of the article.
Charles Darwin didn't know about DNA so he wasn't aware of the power of molecular evolution and he didn't know that we could trace ancestry by comparing sequences.
Darwin didn't know that we would be able to identify and isolate the genes responsible for natural selection.
Darwin's greatest idea was that natural selection is largely responsible for the variety of traits one sees among related species. Now, in the beak of the finch and the fur of the mouse, we can actually see the hand of natural selection at work, molding and modifying the DNA of genes and their expression to adapt the organism to its particular circumstances.So Darwin was right about the idea that natural selection is the mechanism that generates most traits among related species.
Darwin thought that evolution was slow but we now know that it can occur very quickly.
Darwin didn't know about the FOXP2 gene.
Darwin was right about sexual selection.
Darwin didn't know that his blue eyes were due to a mutation in the OCA2 gene but he would be happy to know that the trait probably spread by sexual selection.
Darwin didn't know about genetic switches and he didn't know that changes in gene expression could explain the "humiliating surprise" that we have the same number of genes as a mouse.
Darwin didn't know about Tiktaalik, a transitional fossil that show how fish evolved into amphibians.
Darwin's biggest mistake was his messy ideas about genetics. He didn't know about Mendel and particulate inheritance.
That's about it. Apparently Darwin knew about everything else.