Since somebody, on Twitter, didn’t appreciated my examples in the JSON vs XML fight ( and I just want to remember everybody that I’m not for the former or the latter, without context ), here I post an example that should be a for-real case in favour of XML, applied in the context of evolving a system without breaking existing clients.
You know Twitter, uh?
Twitter lacks of I18N: you can’t selectively filter tweets without recurring to some hacks.
So, when you follow foreign users, you’ll face incomprehensible tweets, sooner or later: the guys of Twitter designed the service this way, so the API probably reflects this business logic.
The Atom representations of public timelines are pretty self-explanatory; so if you want to add the possibility to select a language for the tweet, the Atom would look like:
so, when twitter will add I18N support we’ll probably see something like this: