1. A computer, comprising: at least one processor; at least one computer readable storage medium accessible to the processor and bearing instructions executable by the processor to cause the processor to: receive at least one image of at least one viewer of a display on which content is presented; generate a signal representative of at least one expression of the viewer made at or around the time the content was presented based on the image of the viewer; process the image using facial recognition software to detect at least one of age, gender, race of the viewer; receive metadata identifying the content; and associate the metadata identifying the content with the at least one expression of the viewer and the at least one of age, gender, race of the viewer.