A profile without a photo is like a blind date. You don’t know who you’re speaking to… and after a while, you usually don’t care. Profiles without pictures make your community less personal and less compelling.
This clever plugin can tell whether the member has replaced their default avatar. They won’t be allowed to do anything more on the site until they do.
You can also select whether administrators can be forced to change their avatars. As a System plugin, it will work on every page of the website, including JomSocial and component pages. (The only exceptions are “Edit Profile” pages that might cause infinite loops when the JS Force Fields plugin is also enabled.)