I saw Google's Translation service has a nice API available, was thinking it might not be too hard to a) store the language that each post/reply is written in (grabbed from the user/forum's preferences for language), and then b) on-the-fly translate into the viewer's language via the google API

Has this been considered?

http://code.google.com/apis/ajaxlanguage/documentation/ 

I've just done this in a new site I've been working on for commenting on photos. It was suprisingly easy todo.

I'll give it a go in YAF in the next couple of weeks and let you know how I get on.

Automatic translation can happen due to poor spelling, grammar, or punctuation, and if you wrote correctly it wouldn't think you were speaking a foreign language.
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