Specify blogging language in user profile
Have a field in which you select the language/s you speak; people speaking the same language can find each other more easily.
Say you're trying to learn Spanish - you could then find people who blog in it. It'd be a fun way to help you learn/practise! It'd also encourage lingual diversity (not knowing anyone online who speaks x language doesn't encourage to post in it, I mean).
I see it as functioning just like our profiles' interests: you could click on any of your languages and be linked to a page listing all the users who speak it as well. (Specifying said language/s in "edit profile," though, shouldn't be done with a field in which you actually write; rather, a scrolling list from which you select your language/s. This simplifies everything - no typos, for one, and no confusion as to whether you're supposed to write "français" or "French"!)
Should be implemented as-is.
Should be implemented with changes.
Shouldn't be implemented.
(I have no opinion)
(Other: please comment)