admin Yellowikis:
Under your proposed system users will not have to log on to change the UI. This is clearly a great improvement. But will it be possible to define a default UI language for a particular page? where no preference for UI has been selected?
That is the idea. To quote the proposal:
<< When no user interface language is set, the UI language should be identical to the content language, that is, when viewing pages in English, the UI language should be English; in German, the UI language should be German, and so on. This ensures that each language community can customize the interface messages according to their needs, and emulates the current behavior of multilingual Wikimedia projects with split databases.
Best,
Erik