Love the winter/christmas-y music! The art is nice, and the falling snow is a great addition - helps set the mood.
I'm not sure how to unselect a building that I've selected from the right menu (if thats possible) - it would be nice to be able to do that, so you could check and compare the stats of your different options (or maybe just showing the stats as a tooltip when you hover would work better).
Overall, a very enjoyable game! Good job.