  Study of gravitational-radiation induced merging rates of relativistic binary stars (double neutron stars; neutron star + black hole; double black holes) shows that the first-generation gravitational wave interferometers with an rms-sensitivity of $10^{-21}$ at frequency 100 Hz can detect 10-700 black hole and only $\sim 1$ neutron star coalescences in a 1-year integration time in a wide range of stellar evolution parameters. It is notable that modern concepts of stellar evolution predict that the first detection of gravitational wave will independently discover black holes. 
Black holes and gravitational waves: simultaneous discovery by initial   laser interferometers