Livejournal Hack
I’ve been following the Livejournal hack closely because as someone who runs many services that allow user submitted content, any new developments in XSS are very important to stay on top of. So far the only official technical explanation I’ve seen is here on lj_dev. Since we don’t allow template editing or embedded JS or styles on WP.com I can’t think of any vectors for attack, but you never know with these things. More on moz-binding.