In the following screen shot, one of my posts in chat is accompanied by my gravatar and (part of) my user name. The next one is accompanied by my full name and rep but is missing the gravatar.
Why the different texts? Is there a pattern (does it mean something), or is it random? That part isn't new.
Some image sites used by SE are blocked for me, but I expected the gravatar to be in only one place so that's puzzling. This behavior is new; I used to see my gravatar everywhere and now sometimes I do and sometimes I don't. (Same for other people, but some of them are using the new gravatars and they're always blocked.) Oddly, the "condensed" form (icon, short text) appears everywhere in the chat transcript, but in the live chat it's as shown above.
This screen shot is from Firefox 18.0.1 running on XP. Before taking the screen shot I disabled Stylish and Greasemonkey, the only add-ons I use that seem likely to be relevant. The direct URL for the image, http://www.gravatar.com/avatar/1bfa4ff176b22f138985ddacbc59506f?s=32&d=identicon&r=PG, loads fine in a tab of its own, but does not show up in chat nor next to my name below this post.