By far, my favourite story when telling people about translations in NodeBB was from fairly early on in the project:
One very early adopter of NodeBB was a fan forum for the Kansas University Basketball Team. Their community, KUBuckets, grew very quickly, surpassing our own community support forum, and kickstarted our efforts to optimize NodeBB, as we had never really tested NodeBB at scale*.
At any rate, soon after launch, somebody made an offhand comment asking why the "favourite" button had an English accent. Keep in mind at this point, no internationalization work had been done, so these comments, in addition to several other offhand comments, did help us decide to prioritise i18n in the next release.
Luckily, Transifex has a neat little deal where open-source projects can be hosted for free, so we've taken advantage of that offer. The use of a translation platform can not be understated. Over the next month, we ended up doubling our language count, and fixed up existing languages that had fallen behind.
Since that first comment, surprisingly, nobody else has commented about our use of Canadian English in NodeBB, and as of July of 2014, I'm very proud to say that NodeBB has been translated into 31 additional languages (was 30, actually, until I checked and Romanian had reached 100% translation. Awesome!), with another five languages being translated!
Our biggest hurdle with translations is keeping them up to date after the initial bulk of work is already done. So if you happen to speak a language other than English, why don't you give our Transifex project a look and see if you can contribute back?
* KUBuckets still runs NodeBB, of course, and to date, they have not run into any scaling issues.