Multi language content - Moodle approach

I'd like to get a conversation started about the possibilities for a multilingual content filter in Elgg. We have a good system for translating the environment, but not yet for multilingual content.

Given that social networks (including the one represented by the Elgg Community) are often multilingual, it would make sense to make the content shared on our social networking apps available in multiple languages.

In moodle this is accomplished using a language filter. For example, having written a page in English I would surround that content with a <span> tag including the "en" filter call. The same content in Estonian would be tagged with the "et" filter. English speaking users would see only the english language text.

If the moodle folks can do it, I'm sure it could be done on elgg as well. Any thoughts?