In particular on the <title> element -- this 
corresponds to the head_title slot on the MeTAL 
templates.

In IE, selecting File->Send->Link By Email creates 
an new email message with the same title as the 
current page and containing a link with the same 
name as the current page title. 

I often find myself doing this to point people at 
open or resolved issues. The default "issueN 
editing" title doesn't make for a very descriptive 
window or email title which means I always find 
myself editing the email before sending it.

FWIW, I've customised our local templates to add 
the tracker name and issue title into the title, with 
a slight tweak to handle the case where the issue is 
being created and so doesn't yet have an ID or title:

<title metal:fill-slot="head_title">
 <span tal:replace="config/TRACKER_NAME" />: 
 <tal:block tal:condition="python:    
context.id">Issue <span 
tal:replace="context/id" />: <span 
tal:replace="context/title" /></tal:block>
 <tal:block tal:condition="python:not 
context.id">New Issue</tal:block>
</title>