Another app note from ROHM Semiconductor on various capacitors used for output smoothing. Link here (PDF)
In recent years, it has become a common practice to recommend multilayer ceramic capacitors for the output smoothing of switching regulators due to the stability of their temperature characteristics and the reduction on the mounting area. On the other hand, they are increasingly being replaced by low-cost, high-capacity aluminum electrolytic capacitors and conductive polymer hybrid aluminum electrolytic capacitors.