What are situations with western languages where you'd use HTML 5's Ruby element?

Question

HTML 5 is introducing a new element: <ruby>; here's the W3C's description:

The ruby element allows one or more spans of phrasing content to be marked with ruby annotations. Ruby annotations are short runs of text presented alongside base text, primarily used in East Asian typography as a guide for pronunciation or to include other annotations. In Japanese, this form of typography is also known as furigana.

They then go on to give a few examples of Ruby annotations in use for Chinese and Japanese text. I'm wondering though: is this element going to be useful only for east-asian HTML documents, or are there good semantic applications for the <ruby> element in other western languages like English, German, Spanish, etc.?

Answer 1

As I understand it, ruby annotations are not really relevant in Western languages because Western alphabets are (more or less) phonetic. In Japanese they are used to give a pronunciation guide for logographic characters which don't have obvious pronunciations (unless you've memorized them). I suppose the Western analog would be IPA notation in brackets following a word, but those are rarely used and I don't know if Ruby annotations would be appropriate for them.

Answer 2

                                                                                                                      _{id-ee-oh-SINK-ruh-sees}
Could be useful for people learning English, as our writing system has many idiosyncrasies that make it somewhat less than phonetic.

Answer 3

As a linguist, I can see the benefits in using <ruby> for marking up linguistic examples with various theoretical notational conventions. One example that comes to mind is indicating tonal levels in autosegmental phonology. Here's a quick example I threw together that can be seen in the latest Webkit/Chromium (at least):

http://miketaylr.com/code/western_ruby.html

Currently, this type of notation is left for LaTex and friends, and if on the web, generally a non-accessible image.