Mobile DNA has published an article by Georgia Tech Professor of Biology John McDonald, who led a team investigating why chimps and humans are so different seeing that our genes are nearly identical.  What they discovered is that the regions adjacent to the genes often differ greatly in their DNA sequences (retrotransposons).  Previously retrotransposons have been considered leftover junk from the evolutionary process, but now it is believed that such regions serve as regulators of gene expression, and it is differences in gene expression that determines the differences between chimps and humans.

This is just one more finding in a long list of findings that show supposed junk DNA (which makes up 98% of our genome) actually has a biological function.  This is something Intelligent Design theory predicted, but is quite surprising from a Darwinian evolutionary point of view.