Acceptable Buck Converter Output
Looks good to me, there aren't any frequencies that really stick out, so it looks good. If your running a microprocessor, spurious frequencies can contribute to error by shifting the voltage levels that transistors switch at. If your worried about this board being an unintentional radiator (FCC testing), then it would be a good idea to build\buy an antenna for that oscilloscope and see if the circuit is radiating. 

The microprocessor may have a limit for input ripple, check the datasheet. Then measure the ripple at the power filter cap. If 50mV is beyond the recommendations of the micro, then you'll need more filtering. Either an LC filter on the output or more power filter caps.