Open source Plone, Microsoft Sharepoint and Google Wave are in that respect all potential contenders to KIX. However, none of them are aiming at directly supporting agile distributed integration.
KIX has one unique feature which makes it stand out - it supports the activities and work flows associated with distributed live documents with dependencies between them.
The KIX support for distributed integration across dependencies covers cases when stakeholders
- are geographically distributed,
- are distributed in time,
- or operate under distributed authority, i.e. belong to different organisations even when there are no formal arrangements.