Om CP 4.1 (Joomla 3.3), with Easysocial integration:
1. The avatar displayed for a category list or list of polls is of the current user, not the author of the poll. So for a guest visiting the page, all the avatars are of the default user (/media/com_easysocial/defaults/avatars/user/small.png). If any user logs in, then all the avatars change to that of the logged in user.
2. If a guest user votes on a poll, then the activity stream says:
"voted on the poll..."
It should say "a guest voted on the poll..."