You mean as a user or as a site owner? I asked this question because when I registered here on Q2A's own Q&A forum, I expected my avatar to be automatically filled, because in the past I had already taken the time to set up a gravatar precisely to avoid having to think about that every time I create a new account. I think it should be automatic (opt-out) rather than requiring action on the user and even on the site owner. The opt-in way should of course still be available. Using gravatars by default provides a seamless experience for users who do have gravatars, and no change in current behavior for those who don't, so it's a win-win configuration, as I see it.