This is an ongoing attempt at an algorithmically-generated, readability-adjusted, tree-constrained scatter-plot of the christmas-musical genre-space, based on data tracked and analyzed for 659 christmasy genres by The Echo Nest.
The calibration is fuzzy, but in general up is more christmasy, down is less (although totally christmas-less genres are not even shown); left is denser and more atmospheric, right is spikier and bouncier.
I did not draw the tree-shape, I used math to convince it to self-organize that way. Although drawing it would probably have been faster.
Click anything to hear a nominal christmas song in, or hopefully near, that genre.