1. A computing apparatus comprising: a processor; and a content management service to be operated on the processor to: receive a plurality of content rules, each of the content rules specifying one or more criteria for application of the content rule to one or more instances of content of a plurality of instances of content; identify one or more instances of content that match the criteria specified by one or more of the plurality of content rules; and apply the one or more of the plurality of content rules to the corresponding identified one or more instances of content in a hierarchical manner based on a specificity of the criteria, wherein a rule specifying more specific criteria is applied with priority over a rule specifying less specific criteria.