The Brainstorm prototype calculates muter count, total and GrapeRank-filtered. Same for followers and reporters. Graph databases make it easy to craft queries like this and to play around with more complex ones.

Looks like the Mute-O-Scope casts a wider net in terms of raw data, based on the total muter counts. One of the first decisions of a Brainstorm instance owner/operator will be which relays to draw data from.