Binaries are more fun because they're slighty easier for the earth-based detectors to find and because they're not just sitting still like lumps. Binaries do fun stuff like rotate and inspiral. The detection of a gravitational wave would verify once 'n' for all and without a doubt the existence of black holes, and there are no few people currently developing detectors of all sorts. I should explain the table a bit. In the Galaxy column you'll find the name of the host galaxy, the place where the black hole is.
Some objects belong to both systems.
The Comment column gives anything of note of that particular object, such as a common name or the location. The Type column tells you what kind of galaxy the object is, from Spiral to Elliptical to Irregular. It helps ever so much that we only get one perspective of each galaxy. Distance column gives the distance in light years to the object. Mass refers to the mass of the black hole, not the host galaxy and is given in the units of solar masses.