Also, avatars can now be up to 500x500, for fancy background stuff I'm still working on. You can see a demonstration on Rhetorica or Nessari. I'm going to switch away from CSS blurs for efficiency, though; it's really slow on Firefox. To enable this on your own page, upload a larger 500x500 avatar, then enable "user page decorations" on the user profile edit page. (Hint: click "More" next to the submit button.)