In reply to Marko Heijnen.

Regarding the statistics: When discussing a new feature, should we watch at the percent of users *already using* that feature through third-party implementations, or at the percent potentially benefiting from it?

I don't have numbers for the first part – stats of major multilanguage plugins may provide an estimate. Regarding the potential: even in the US, with just one official language*, about 20% of the population is multilingual. Not speaking even of China or India.

*Edit: Wikipedia proves me wrong :)