The "feeds" collection is all of the socially shared items across any service, facebook newsfeed, twitter timeline, foursquare recents, etc.
It consists of a primary type called an "item" which can have an array of "responses" that are comments, likes, retweets, etc from other people.
The goal is to dedup cross-posts to multiple networks from one person, particularly things like a foursquare checkin.
Notes:
id references and keys cross-collection reference storage with links link based dedup of foursquare dedup uses keys as guids across networks and for text matching variations /update takes type arg for individual updates idrs as via, no original storage prioritization scheme in merging items generic from object, list of froms references array of all sources generalized responses and top-level statistics