[psc]

Never knew, do you a have a source on this? Not that I don't believe you, I just want to read more about it. A Chrome extension that shows you if STARTTLS is being used would be really neat.

[jlgaddis]

Source: Me, who runs (among other things) mail servers for an ISP.

ETA:

    Received: from mail-pd0-f169.google.com (mail-pd0-f169.google.com [209.85.192.169])
    	(using TLSv1 with cipher RC4-SHA (128/128 bits))
    	(No client certificate requested)
    	by MAIL.MYDOMAIN.COM (Postfix) with ESMTPS id 1BBFA2909
    	for <[e-mail]>; Thu, 23 Jan 2014 23:00:32 -0500 (EST)

[iso-8859-1]

How does Chrome have anything to do with this?

[ams6110]

This is a server thing. Your mail client, web-based or otherwise, wouldn't know.