Text about "language information data category"?

Hi Richard, cc'ing to public-i18n-its,

Since you proposed the language information data category, I was
wondering if you want to produce some text for the "language
information" data category, see the empty section at

http://www.w3.org/International/its/itstagset/itstagset.html#datacat-lang

If you don't want to write the section: What would you want to have in it?

Thanks,

Felix