So far, no scientist has been able to specifically turn any adult stem cell population into good populations of motor-neuron cells. Remember that ALS patients tend to die within four years. Opponents of therapeutic cloning need to remember that we do not have time to waste.
The pressures for human cloning are powerful; but, although it seems likely that somebody, at some time, will attempt it, we need not assume that it will ever become a common or significant feature of human life.
Successful cloning of an increasing number of species confirms the general impression that it would be possible to clone any mammalian species, including humans.