1. A method for brokering facilitated publisher collaboration in a publish-subscription (pub/sub) messaging environment, comprising: receiving, on a broker system that intermediates between a set of publisher systems and a set of subscriber systems, messages sent by every one of a plurality of publisher systems in the set of publisher systems to designated ones of the set of subscriber systems; determining, on the broker system, that a first publisher system and a second publisher system in the set of publisher systems in the pub/sub environment are potential peers based on publisher information; communicating, based on a determination that the first publisher and second publisher system are potential peers, a suggestion from the broker system to the first publisher system that a peer relationship be established with the second publisher system; forwarding an invitation for the peer relationship from the first publisher system to the second publisher system; establishing a peer-to-peer (P2P) communication channel between the first publisher system and the second publisher system; identifying a set of data included in messages sent by both the first publisher system and the second publisher system using the P2P communication channel; caching the identified set of data in a common cache that is a central cache accessible to the first publisher system and the second publisher system using the P2P communication channel; generating a unique identifier corresponding to the set of data, the set of unique identifiers identifying the set of data as cacheable; communicating the unique identifier to at least one of the first publisher system and the second publisher system; generating a message containing the set of data using the unique identifier to one or more subscriber systems in the set of subscriber systems receiving an abbreviated message on the broker system, the abbreviated message having the unique identifier in place of the set of data; retrieving the set of data from the cache using the unique identifier; replacing the unique identifier with the set of data to yield a completed message; and sending the completed message from the broker system to a set of subscriber systems.