W37 novelty? Cookies and RSS feeds
Don't know exactly how new this is, but I think it is fairly new (maybe W37). I suddenly notice that cookies are sent when fetching RSS feed items from "News & Blogs" in the mailer (so that, for instance, MediaWiki diffs opened in a mailer Message window from the site's RSS feed now appear in my favourite "CologneBlue" MediaWiki skin and not in the default "Monobook" skin when I'm already logged in to the corresponding site.)
For my use case, the above is a plus. Maybe some people would have the opposite opinion. Don't know if governed by a preference.
Certificates and icons
I see the "Larry icon" in "View Page Info => Security", green on https://addons.mozilla.org , blue on https://bugzilla.mozilla.org (and at least one non-mozilla https page), grey on http (without s) pages, in the Modern theme (didn't look at Default) but not in EarlyBlue (didn't look at LCARSTrek). Don't forget to add those icons when you pop the maxVersion to 2.0 (currently 2.0b1) (and I know you're busy -- no rush ).
What I do see even in EarlyBlue is a "green Larry" on the URL bar for AMO, together with "Mozilla Corporation" on green background next to the (green locked) statusline padlock.