I trust the intent here is to emulate IE behaviour, because innerText does not seem to have a standard specification.
It seems that there is currently a difference in behaviour though, take the following HTML
<td><span style="display:none">02005-06-02</span> <a href="/wiki/June_2" title="June 2">June 2</a>, <a href="/wiki/2005" title="2005">2005</a></td>
in IE innerText should result in: "02005-06-02 June 2, 2005" (at least earlier versions, I did not test in IE7)
on Safari 3.0.2 i get: "June 2, 2005"
Created attachment 15725 [details]
Test case from Comment #0
Both Safari 2.0.4 (419.3) with original WebKit and Safari 3 Public Beta v. 3.0.2 (522.12) with a local debug build of WebKit r24749 on Mac OS X 10.4.10 (8R218) both result in:
Actual td.innerText = 'June 2, 2005'
Firefox 18.104.22.168 on 10.4.10:
Actual td.innerText = 'undefined'
As a work around, you can can use the textContent attribute to get the same result as innerText on IE.
This workaround is now used in wikipedia http://svn.wikimedia.org/viewvc/mediawiki?view=rev&revision=24647
However, i still think that if we implement IE specific behaviour, it should either work exactly like that, or not be implemented at all.