1. A method in a content recommendation computing system, the method comprising: presenting a first user interface control that is configured to create a new entity collection in response to received user selection of indications of named entities and suggest one or more additional entities to add to an existing collection; presenting a second user interface control that displays information about collections created by multiple different users of the content recommendation computing system; defining, responsive to user selections of indications of named entities via the first user interface control, a collection including multiple entities that are each referenced by one or more of multiple content items indexed by the content recommendation computing system and that are each electronically represented in the content recommendation computing system, the collection being separate from the multiple content items indexed by the content recommendation computing system; under control of the content recommendation computing system, automatically recommending one or more additional entities to be added to the collection based on the multiple entities of the collection, by: determining shared characteristics of the multiple entities, wherein each shared characteristic is the same for each of the multiple entities of the collection, the shared characteristics including common facets and common key terms common to the multiple entities of the collection, wherein the common facets are category values, type values, and/or characteristic values of the multiple entities and are sub-type values of a top-level entity type electronically represented by the content recommendation computing system; determining a plurality of entities that includes at least a first entity that appears in a content item in a relationship with one of the common facets, a second entity that appears in a content item in context with one of the common key terms, and a third entity that appears in a content item in a relationship with one of the multiple entities and in context with another of the multiple entities, wherein the first entity appears in a content item in a relationship with one of the common facets when the first entity appears as a first subject or object of a subject-verb-object relation present in the content item in which the one of the common facets appears as the other of the subject or object of the first subject-verb-object relation; and ordering the determined plurality of entities, based on entity frequency counts of frequency each entity appears in the indexed content items and on whether the determined plurality of entities share one or more of the common facets; presenting on the first user interface control the ordered plurality of entities as suggested additions to the collection; modifying the collection by adding one of the ordered plurality of entities to the multiple entities of the collection, the added entity selected by a user via the first user interface control; automatically processing the modified collection to determine one or more of the multiple content items that are related to at least some of the multiple entities of the modified collection, wherein processing the modified collection includes determining whether one of the multiple entities appears in a content item in a relationship with a facet common to entities of the modified collection and in the content item in context with key terms common to the entities of the modified collection, wherein the one of the multiple entities appears in a content item in a relationship with the facet common to entities of the modified collection when the one of the multiple entities appears as a subject or object of a second subject-verb-object relation present in the content item in which the facet common to the entities of the modified collection appears as the other of the subject or object of the second subject-verb-object relation; and recommending the determined one or more of the multiple content items.