On Fri, 24 Mar 2006, Ian Hickson wrote:

> According to my studies it's used in around 0.1% of the Web's pages. One
> in every thousand pages isn't bad, given how few pages could be expected
> to be defining terms; In particular, it's used more than <ins>, <del>,
> <var>, <samp>, <bdo>, etc.

I can't argue with your statistics - the Google analysis
http://code.google.com/webstats/2005-12/elements.html 
does not cover the <dfn> element. But I think I have almost never seen 
<dfn> used anywhere except on my own pages and on sites like W3C (and 
tutorials that describe the <dfn> element and illustrate its use) - and I 
have read other people's HTML code quite a lot.

Assuming that the figure 0.1% is representative, is it small or large as 
compared with the expected frequency of pages that actually contain 
definitions of terms? After all, what matters - for purposes like 
developing browsers and search engines - is the probability that you can 
actually locate defining occurrences by looking at markup for them
(at present, <dfn> and <dt>). Even if you get a large amount of 
information that way, is it enough if it is just a small fraction of pages 
that actually define things?

-- 
Jukka "Yucca" Korpela, http://www.cs.tut.fi/~jkorpela/