From InfoWorld: “P2P is moving beyond collaboration and file sharing to serve as connective tissue in virtual datacenters and storage, BPM (business process management), and composite applications.”
The article states that P2P is taking on several hybridized forms:
Pure peer-to-peer is completely decentralized and characterized by lack of a central server or central entity; clients make direct contact with one another.
Computational peer-to-peer uses p-to-p technology to disseminate computational tasks over multiple clients; peers do not have a direct connection to one another.
Datacentric peer-to-peer is information and data residing on systems or devices that is accessible to others when users connect. It is sometimes called peer-assisted or grid-assisted delivery. Applications include distributed file and content sharing.
Usercentric/hybrid peer-to-peer involves clients contacting others via a central server or entity to communicate, share data, or process data. Often used in collaboration applications.