Electronic content ranking based on distribution and consumption

A content distribution system comprising:

• a content subscription manager configured to control distribution of content items provided by content producer computers to content consumer computers via a computer network;
• a message tracking engine configured to track indications of different interactions with content items contained in messages distributed by the content subscription manager, the different interactions with content items occurring at the content consumer computers;
• a search engine configured to index content items and output ranked indications of at least some indexed content items in response to search queries, wherein the search engine comprises a presentation engine configured to track indications of different interactions with indexed content items occurring at the content consumer computers;
• and
• a content ranking engine configured to receive indications of different interactions from the message tracking engine and the search engine, the content ranking engine configured to rank the content items based on the received indications of different interactions with content items occurring at the content consumer computers.