I love human evolution :) And the results that have come out recently about common genes between out-of-African humans and neanderthals has been pretty awesome (summary: 1% - 4% of non-African humans carry some genes that neanderthals also carried, which might suggest interbreeding around the Levant). This article
tries to suggest a less sensationalist couple of explanations for the genetic similarity, but frankly all the options are pretty damn sexy to me :) - there was a significant interbreeding event during the expansion around 70K years ago, or there was an earlier interbreeding that got pulled back into Africa (less likely due to pinch events), or the African populations have *lost* those genes for some reason.
In any case, having a wider variety of human genomes can only help with our understanding of evolution and what our genes do. Awesome.