Whichever is better depends on the area.

If you live in an area where there is good cable, but most of the people are computer illiterate and probably won't spend their evenings downloading the latest episode of Bubble Gum Desire Tentacle Rape Ninja anime, then cable is the best. Otherwise, you better get DSL.

For example, DSL might be better for the west coast, and cable might be better for the redneck South.