A power supply decoupling cap first and foremost should have a low impedance for the frequency which it should short-circuit. Hence electrolytic capacitors (ELCOs) in the 100µF range are good against 100/120 Hz line frequency interferences, but not so good against interferences in the middle and high (RF) frequency ranges because of their (relatively) high series-L and -R (ESR) impedances. For the decoupling of such frequencies, mostly ceramic caps are used (in parallel to a possible ELCO).
It depends on the frequency, which values will be chosen: To decouple audio amplifiers with frequencies in the 10kHz range, a few additional 10µF ELCOs on board could be perfect, for converters in the 100kHz range, some 1µF ceramic caps would probably fit better, against 1..10MHz distortion ≈100nF cercaps would be fine, and for decoupling several 100MHz interferences probably 1..10nF cercaps would do easily -- and perhaps even better than larger ones.