Please note that there are no actual plans for this at this time.
MediaWiki: Features - Handbook - Sources - Bug/Feature Submissions - The team
MediaWiki 2.0 is the proposed next-generation incarnation of MediaWiki. Any fundamental redesign or major new concept should be implemented as part of MW2, rather than the current 1.x branch.
For now, suggested components of MW2 are:
- advanced content transclusion (images and text)
- peer review markup language (for highlighting factual statements and associating them with sources)
- full internationalization - multiple languages in a single wiki
Note that not all of these components has to work fully at the time of release, but the database architecture should accommodate all of them.