Open Archaeology is an umbrella-project that will host a number of sub-projects. While functional at a component level these sub-projects are intended to interoperate creating a complete AIS (Archaeological Information System), including the components necessary to manage the organisation carrying out the archaeology.
Open Archaeology is first a concept or philosophy, with the 3 primary strands of open data, open standards and open source. More information can be found at the Open Archaeology homepage (http://openarchaeology.net). The philosophy has been around for some time; the software project started during 2006 by Oxford Archaeology (http://thehumanjourney.net), and was moved to Launchpad in 2007.
The initial code contributions came from Oxford Archaeology as part of that organisation's commitment to the Open Archaeology philosophy; there are many more people and organisations interested in participating. If you are one of them, don't hesitate to join in!