The first one is danced to a very popular candombe, great tune. I also feel that this kind of music has a similar feel to salsa etc.
The guy dancing is something of a king of milonga con traspie in Buenos Aires. I did a class with him once, it was funny. I barely knew any milonga but ended up dancing with him quite a lot during the class. He was very serious about teaching us and it was a great experience.
I'd like to know more about candombe too and the difference between candombe and milonga. How do you tell that it's a candombe and not a milonga playing? I don't know much about music - I can sometimes hear that something is a candombe, but I'm not sure why. And are they both danced as a milonga or do people actually dance candombe too (like you can dance canyengue)?